Georg Friedrich Meier: Thoughts on the condition of the soul after death (1746)

Meier’s Gedanken von dem Zustande der Seelen nach dem Tode is a rare book for its time, since although it studies the condition of the human soul after death, it does not try to demonstrate that this soul will continue to exist then. Indeed, he says, most of the demonstrations suggested for the immortality of our souls seem convincing just because the conclusion has already been accepted. We believe in the afterlife, because the idea agrees with our hopes, and indeed, we picture the afterlife to be as we would like it to be: Meier mentions a noble who was certain that in the afterlife souls of the nobility won’t have to mingle with souls from the lower classes.

Meier still makes sure to ascertain that he isn’t trying to disprove the immortality of the soul either. The reason for such an explanation is clear, since Meier speaks of the pressure of religious zealots, who censure everyone who even appears to go against such central religious dogmas. Meier assures the reader that he believes in the immortality of the soul and the final judgement of all humans, just because the Bible has taught him so. He even admits that we can be morally certain of this immortality and commends anyone who wants to go even further and demonstrate it with complete mathematical certainty.

Still, Meier says, the aim of his work is to show that such a demonstration is impossible for human beings, although, as he immediately adds, human reason is not inevitably led to doubt the immortality of the human soul. He will even analyse some suggested demonstrations and show where they fail to prove what they set out to prove. Finally, Meier concludes, his work will make it clear that nothing certain can be revealed about the condition of our soul after death.

Meier emphasises that his work has not been motivated by mere arrogance. Instead, he wants to raise the value of faith and scripture by lowering the worth of the human reason. Furthermore, Meier insists, the distinction of the faith and the reason also defends the faith: if one would think that belief in the immortality of the soul is based on nothing else than supposed demonstrations of reason, the weaknesses of these demonstrations would place the faith also in jeopardy.

Meier scorns all those who prefer leaving people with the incorrect opinion that demonstration of the immortality of the soul is possible in the name of religion and morality. On the contrary, he says, religion and morality do not need such weak defences. Immortality does motivate us for morality and religion, but motives need not have mathematical, but mere moral certainty.

Morality specifically, Meier thinks, has motives, even if we didn’t believe in immortality, because it has good consequences even in this life, and at least philosophers are equipped to understand these motives. Even if other people would not recognise these motives, Meier says, they still wouldn’t all become murderers and robbers, if they did not believe in the immortality of the human soul. His justification is that people generally do not act on the basis of some theories, but on the basis of their passions and inclinations. Furthermore, he insists, universal lack of morality could not occur, since, for instance, a universal disregard of property rights would soon collapse, since no one could make sure that they could keep on to what they had stolen from others.

Even religion could exist with the belief in human immortality, Meier says. True, he admits, most non-believers in immortality are atheists. Still, the demonstration of God’s existence is independent of the truth of our immortality, and when we accept the existence of God already, we always have to accept religion also.

Christian August Crusius: Draft of necessary truths of reason, in so far as they are set opposite to contingent ones - Spirits as part of moral universe

Crusius’ work culminates on the question of properties that free spirits have because of their moral attributes. He notes that such properties are essentially based on the infinite perfection of the divine will. Particularly important in this context are the divine holiness, the divine goodness and the divine righteousness. Since God necessarily has these properties, Crusius argues, free spirits must also necessarily have the properties based on these divine properties.

The properties Crusius is speaking about fall roughly into two categories. Firstly, since God wants the whole world to be perfect, Crusius begins, he also wants that free spirits would act in accordance with the rules of perfection, that is, that they would act virtuously. Of course, Crusius adds, this does not mean that God would force them to act virtuously, because then they would not be free beings. What God can do is to ensure that virtuous spirits will be happy and that those violating laws of perfection will be punished. All free spirits are thus necessarily subjected to the divine law, which God expects the free spirits to follow obediently.

In addition to this subjection to divine law, Crusius speaks of one other property, that is, immortality. He adds that it is not enough that a spirit is indestructible, in order for it to be immortal, but it must also be constantly alive and conscious of its own state. Thus, a free spirit is not by its essence immortal, even if we ignore the fact that God could annihilate even free spirits, because even hostile conditions of bodies can make spirits unconscious. Hence, Crusius concludes that we must show that God wants to prevent all the obstacles that could hinder the immortality of free spirits.

Crusius is particularly adamant that the Leibnizian notion of a pre-established harmony of souls and bodies does not in any way justify the immortality of free spirits, even if it would be true, which Crusius obviously does not accept, because he believes that souls and bodies do interact with each other. Indeed, he continues, since Leibnizians have to assume that before its harmonisation with a body the soul could not yet represent anything, it would be analogously plausible that the soul would lose all representations after this harmonious correspondence was over after the death of the body.

Crusius’ own justification of the immortality of free spirits is ultimately based on their being the main purpose in God’s plans for the world. In addition to freedom, God has given free spirits abilities to reason and abstract, consciousness and drives toward perfection, communion with God and virtue. All these attributes, Crusius argues, contribute in free spirits aiming for an indefinitely extended life in constant pursue of evermore perfect stages of virtue, which in fact should be the highest purpose of the world. If free spirits would not be immortal, God would have given these abilities in vain and the main purpose of the world would be defeated.

Crusius still considers the possibility that only some spirits would be able to reach immortality, while others would only serve as means for the blessed immortals to reach their goal. Crusius thinks this possibility is unbelievable, since God would not have given freedom to such beings that were only means for other beings. Indeed, Crusius points out, even spirits who have acted morally wrong have to be immortal, so that God can punish them for the whole eternity.

A more difficult problem Crusius faces when he considers the fate of babies who die before they could have developed their reason and thus their ability to act freely and make moral choices. Although he does not have even a very probable argument to back it up, Crusius does suggest that these children will probably continue living, even if their life after death will probably be less perfect than with those who have reached the maturity of moral beings.

Crusius is also uncertain what the life after death will be like. We might need no body anymore or we might receive a new kind of body or one exactly like the one we used to have - or we might go through all of these stages at different stages of our life after death. Crusius does insist that the life after death won’t include long periods of sleeplike condition, while waiting resurrection, as some Catholic thinkers had suggested. Crusius reasoning is that such long periods of passivity make us lose our abilities, so it would probably be harmful to our consciousness also.

Christian August Crusius: Draft of necessary truths of reason, in so far as they are set opposite to contingent ones - What is spirit like?

If in the previous chapter Crusius intended to explain the essence of spirit, in this chapter he wants to outline the basic features of a spirit. In effect, he has to describe in more detail the two basic capacities that distinguish spirit from mere matter, that is, understanding and will.

Starting with understanding, Crusius says that every idea a spirit has cannot be something passive. If there was a passive idea, he justifies his statement, it would have to be caused either by an external or by an internal activity. If an idea was caused by an external activity it would have to be either movement or caused by movement, because external interaction occurs only via movement. Both possibilities, of course, contradict the very immateriality of a spirit, Crusius notes. On the other hand, if an idea was caused by an internal activity, it would again be caused by movement or by some other activity belonging to the spirit. The former possibility is again an impossibility for Crusius, while the latter possibility he rejects, because ultimately all spiritual activities presuppose ideas.

Although ideas are always activities, Crusius continues, they can be directly generated by God, who supposedly does not act through movement. Furthermore, he adds, ideas can be modified by other activities of spirit and their generation, forcefulness and duration can be connected to external conditions.

Furthermore, Crusius notes that while all spirits have understanding or capacity for thinking ideas, only some spirits have reason, that is, an understanding so developed it is able to consciously know what is true. To have a reason, it is not enough that a spirit can have ideas, but these ideas must also be able to continue for a while. In addition, a spirit with a reason must be conscious of itself and it must be able to make abstractions. Finally, Crusius concludes, a finite spirit cannot have reason, unless God has given it the capacity to think, distinguish and combine ideas in a manner that it can recognise signs of truth in them by imitating divine understanding.

Crusius emphasises that if a finite spirit is capable of reasoning, its capacity of understanding is not derived from a unique force, but from a sum of many fundamental forces. The only other option, he points out, would be that the fundamental force would be the general force for thinking or knowing truth. Crusius rejects this possibility, because our ideas are so multiform that they cannot all have the same source. He especially points out that it is a very different matter to have an idea and to be conscious of this idea, because one can e.g. be angry without being aware of being angry.

If Crusius defined understanding as a capacity to have ideas, he defines will as a capacity to act according to one’s ideas. Every spirit must have a will, he adds, or otherwise its understanding would have no purpose. Every act of will presupposes an idea and therefore, Crusius insists, will as such is called a blind force.

Crusius is adamant that will requires fundamental forces distinct from those required for understanding, because otherwise will would be just a modification of understanding, which he has already denied. He especially objects to the idea that will could be understood as deriving from a representation of goodness, because good wouldn’t even be a meaningful concept without will. He does admit that the representation of goodness can awaken our will, but he doesn’t think this would yet reveal what will is. Crusius doesn’t even accept the Wolffian idea that the representation of goodness together with conatus or innate striving toward goodness would be enough to define will, simply because Crusius regards conatus as an unfamiliar manner of referring to will.

Every will must will something, Crusius points out, that is, it must be directed by specific ideas, which the will then strives to achieve by action. When such striving continues for a longer period of time, Crusius calls it a drive. Will must then have drives, and even, Crusius says, some fundamental drives, from which other drives are derived. Actions caused by the same fundamental drive can have various grades and directions, thus, Crusius concludes, only few fundamental drives are required for manifold variations in actions. Since a state of a spirit can be in accordance with a fundamental drive, in opposition to it or neither, we can speak of pleasant, unpleasant and indifferent states of mind or feelings. A reasoning spirit, Crusius adds, is also conscious of its state being pleasant and unpleasant, which makes it possible to speak of pleasure and pain. For animals, on the other hand pleasant and unpleasant sensations act then as mere physical causes.

Crusius notes that all animals should control their body and so they must have drives concerning the body and therefore also an idea of their body. Reasoning spirits, he continues, should also have fundamental drives that serve their moral perfection. Such fundamental drives include a drive for perfecting one’s essence, a drive to love other spirits and a drive to fulfil obligations toward God or conscience.

In addition to fundamental drives, Crusius insists, at least reasoning spirits must also have freedom. Even freedom, Crusius admits, does not do things completely without any reason, but it has to be guided by motives. These motives just do not determine the free will to do anything, but just make it inclined to something, leaving the will the final choice whether to pursue these inclinations. Free will can also boost smaller inclinations against stronger inclinations. Yet, Crusius notes, free will of finite spirits must also be finite and can thus be overcome by strong motives.

Activities of a spirit form a clear hierarchy, Crusius says. For instance, movement is the lowest kind of activity, which serves both understanding and will: Crusius again emphasises that the spirit should be able to move its own substance. Of the two other activities, on the other hand, understanding is subservient to will. This does not mean that e.g. laws of truth should be dependent on arbitrary choices of the will. Instead, it means that understanding ultimately does what the will wants, and indeed, for this reason we can speak of the moral perfection of understanding: e.g. a failure to develop one’s understanding could be taken as morally evil. With free spirits, Crusius concludes, freedom is the highest activity, which the fundamental drives should serve.

Crusius notes that there is a certain ambiguity in the concept of a purpose, which he defines as something that a spirit wills. He explains that we might be speaking of a subjective purpose or our own activity of desiring something, of an objective purpose or the object which we specifically desire, and finally, of a formal purpose, by which he means a relation between the subjective and the objective purpose. Purposes form a hierarchy, Crusius explains, since one purpose could be desired because of another purpose. He is convinced that such a series of purposes cannot continue indefinitely, but there must be one or several final purposes, which are desired for their own sake and not to fulfil another desire.

It is common knowledge that we often cannot directly achieve our purposes and so have to use some means to do this. Crusius notes that actually means is an ambiguous concept: it might refer to material means or the mediating cause used for furthering the purpose, but it could also refer to formal means or the activity of using the material means. Crusius also remarks that means can be divided into means in the proper sense, which are active causes that have in itself the power to further the purpose, and mere conditions, which do not have the power to further the purpose, but are still required by other causes to further the purpose. In order to be a proper means, Crusius adds, means must, firstly, make something happen to further the purpose, when so directed by a spirit, secondly, bring about something that the spirit wants before wanting to use the means, and finally, be used by spirit because of desiring the purpose. Thus, if a spirit doesn’t intend to use something because of a purpose, but for a completely different purpose, and this something happens to further the purpose, spirit hasn’t used it as a means for the purpose, but it has been a mere accidental intermediary cause for the purpose.

The notion of spirit is closely connected to that of life. Crusius defines life as a capacity of substance which enables it to be active from an internal ground in many, qualitatively different ways. The seemingly innocuous demand that activities enabled by life should come in many different forms actually implies that these activities cannot be distinguished by mere quantitative means, like spatiotemporal terms or grades of strength. Thus, these activities, and so also life, cannot be based on mere motion and can therefore belong only to spirits. Crusius notes that his concept of life excludes plants, which do not have spirit or soul. In fact, he adds, only spirits really have life, while animal bodies have life only in the sense of being connected to a spirit or a soul.

Crusius also notes that life is more of a continuum, with some substances being more alive than others. Thus, while one substance is alive in the sense that it has all the capacities required for living, another would be alive in a stronger sense, if its capacities of life are truly active. This higher phase of life begins, Crusius suggests, when the will of the spirit becomes active. Depending on the perfection of the will, life can then be also more or less perfect, and the highest type of life is the life of a free spirit.

While God can be alive and still have only one fundamental force, a finite living being must have several, in order to create a qualitative manifold of activities, Crusius insists. These fundamental forces must then be interconnected in the sense that one force is a condition or an object of an activity based on another force. Such an interconnection of forces then modifies the activities enabled by these forces and thus creates the manifold of activities required of a living being. These interconnections are then, Crusius concludes, controlled by laws, some of which describe interactions of spiritual activities, while others describe their interactions with the body and the material world.

Crusius goes through several of these interconnections of spiritual activities. Thus, he notes that force of will is dependent on the force of understanding, and especially, free will requires an ability of abstraction and consciousness of oneself. Other examples include when a drive for some purpose awakens a drive for the corresponding means or when thinking a certain idea activates also some other ideas through association.

An important type of interconnection connects the higher powers of the spirit to its capacity to move. These connections enable external sensations, in which ideas are not literally caused e.g. by our substance moving because of external objects, Crusius notes, but they still are conditioned by the presence of such a movement. Such an external sensation can even be an occasion for a substance becoming alive in the stronger sense, that is, for the substance activating its powers of life. The connections with the capacity of movement also explain why movements of the body can hinder our thinking and why spirits can finally return to the same inactive state in which they were, before having the first sensation. Although such interconnections are then possible, Crusius points out that a finite spirit can also be independent of the movement of its substance, which means that it would be constantly alive.

As an important instance of interaction with external things, Crusius points out that in order to interact with one another, spirits should be able to communicate with one another. With mere animals, this communication can happen through expressions, while spirits with reason are also capable of languages using words that express abstract thoughts. Both kinds of communication use the material world and its movement, but Crusius thinks that God is capable of a more direct sort of communication, in which thoughts are awakened straightaway in the other spirit.

Although activity of one power of spirit would be a condition for another power becoming active, it is still not necessary that when the first power stops its activity, the second should also stop: in some cases it might do this, in others not. This distinction between the behaviour of the powers is important for Crusius especially in cases where external sensations are a condition for the spirit becoming alive in the stronger sense. Some spirits might be passive in the sense that their activities both begin when certain sensations occur and end when these sensations stop. Other spirits, on the other hand, might be capable of independent activity in the sense that while their activities are awakened by sensations, these activities can still continue even after the corresponding sensations have stopped.

With a spirit capable of independent activities, these activities can then continue for a long period of time. Crusius emphasises that such continuing activities are not free choices, which always endure only for an instant. An enduring activity can then be strengthened by new sensations awakening similar activities and this strengthening makes it more probable that the activities lead to effects. In effect, Crusius says, such repetition of activities makes them habits. With human beings, some of these habits might have even been generated, when the human was still a foetus, and could thus be called inborn habits.

Crusius notes that spirits of the world can now be divided into four different classes. The two first classes consist of passive and independently active spirits, that is, firstly, a) spirits that live in the proper sense of the words only while they have sensations, and secondly, b) spirits that are awakened by sensation, but continue to live even after the sensations have stopped because of their inner activities. Both of these classes consist of spirits that do not always live, but must be awakened to life. The two other classes consist then of spirits that do live, even without the help of external sensations. These two classes are then distinguished from one another by c) one still having external sensations, d) the other class not.

Whatever the class a spirit belongs to, Crusius says, it is always a simple substance and thus immaterial. Crusius does admit that God could give a partless element of matter capacities to think and will. This wouldn’t still mean that God would have created a material spirit, but only a transformation of matter to spirit.

Christian August Crusius: Draft of necessary truths of reason, in so far as they are set opposite to contingent ones - What is a spirit?

The final part of Crusius’ metaphysics consists of what he calls pneumatology, that is, a study of finite substances that can not just move, but also think and will. Crusius notes that no matter what the world is like, it must contain such substances - they are supposed to be the purpose of the world - thus, pneumatology should be included in a metaphysical cosmology. Once again, pneumatology should study only the necessary properties of these substances, not those dependent on the contingent features of the world.

Despite emphasising the apriority of pneumatology, Crusius begins with an empirical study of activities we find in our mind. We perceive in us thoughts, he starts. Some thoughts we have while we are awake and they represent what is immediately present to us: these are what is in German called Empfindung - a word that could be translated, depending on the context, as sensation or as feeling. Whatever the translation, Crusius classifies these sensations or feelings into external - those representing a thing outside us with the help of sense organs - and internal - those representing the thing that thinks in us. Through the inner sensation or feeling, Crusius states, we are conscious of ourselves, of our thoughts and of our state of mind.

Crusius goes on describing further capacities of thinking we have. These include memory – a capacity to return to thoughts we once had and thus represent things we sensed, although they are now absent – imagination – capacity to move from one thought to another – abstraction – capacity to divide thoughts into their constituents, for instance, to think of a subject without its properties – capacity to make propositions, that is, to note relations between thoughts, and a capacity to make deductions. These capacities, Crusius notes, are all explained in terms of thoughts or representations, which is a fundamental concept that cannot be explained further.

In addition to thinking, Crusius continues, we find in ourselves something else. We are pleased when we achieve something we want, and we feel pain when we face something we wanted to avoid. We also note that we can control our thoughts, our body and even our desires. All of these, Crusius says, show that we have will, that is, a force of acting according to our representations. Willing presupposes thinking, since we need to have representations, before we can will, Crusius adds, but mere thinking is still not enough for willing. Willing is hence something more than thinking, but this something more cannot be defined.

In addition to thinking and willing, we also have a notion of moving, Crusius says, since we can both see things outside us move and we can move ourselves and our body. Furthermore, he at once adds, we immediately know that movement is something different from thinking and willing and cannot be even their cause. This basic fact, guaranteed by very clear inner feeling, Crusius insists, is the only proof we need against materialism: thinking and willing are not mere movement of matter. No matter how fine the matter is, Crusius states, it can never think or will anything.

Crusius suggests that the central confusion that makes one believe in materialism is that the word “representation” suggests that a thought is like a concrete picture in the brain. He notes that the same confusion can be found also with anyone endorsing Leibnizian pre-established harmony, which states that any representation in the soul corresponds to a material idea in the brain. Crusius argues that a machine could not change pictures as rapidly as we change from one thought to another. Furthermore, he notes that no machine could store pictures for as long a time as our memory does. Indeed, he adds, the brain would soon be filled, if we had to insert pictures in it any time we have thoughts. Abstract ideas especially appear to be such that could never be represented materially. And if no other argument works, Crusius concludes, we can always note that materialism would destroy the freedom of our will and thus make morality and religion impossible.

In addition to this fundamental confusion, Crusius considers other arguments of materialists that he considers fallacious. Most of these involve the obvious fact that the body appears to affect our state of mind, for instance, that a physical sickness makes it difficult to think. Crusius’ answer is that these effects can as well be explained by the close interaction of the spirit and the body.

Crusius notes further that materialists apply arguments involving biology: they state that supposedly thinking and willing beings (e.g. worms) can come out of rotting meat and that parts of worms can still continue their movement when cut apart. The first argument Crusius deals very quickly: worms are not spontaneously generated by the rotting meat, but very small eggs of worms just grow faster, when coming in contact with the warmth and moisture of rot meat. In the case of the second argument, Crusius just points out our ignorance on why the worms can do this - perhaps the movement of a dissected worm is just a mechanical reflex that does not require free will.

In addition to speaking so fervently against materialism, Crusius is eager to state that it is not materialistic to assume that thinking and willing substances can move things. Thinking and willing substance can be spatial and impenetrable, because these characteristics do not form the essence of material things. Some things in the world - like stones - have only a capacity to move, while we humans can move, but also think and will.

Thinking and willing are characteristic not just of humans, Crusius says, but other organic bodies appear also to move as guided by a thinking and willing substance. These organic bodies must also have such a guiding substance or soul, Crusius insists. Together, the soul and the body form an animal, and we humans are then the most perfect animals. Crusius is certain that thinking substances, both those of humans and those of other animals, can exist without being connected to a body. Then these substances just shouldn’t be called souls, but spirits (Geist). Even God could be called spirit, since God can think and will, although not move.

We have already noted that a willing substance must think, but must every thinking substance also have a will? Crusius admits that this is technically a possibility. Yet, from a wider perspective, such merely thinking substances cannot exist. God does nothing without purpose, and what purpose would such a non-willing thinker have? In other words, Crusius appears to say, thinking is done in order to help willing – for instance, in choosing the right means for achieving what we want – and mere thinking by itself would not be enough.

Christian August Crusius: Draft of necessary truths of reason, in so far as they are set opposite to contingent ones - Laws of movement

In every world, Crusius notes, things interact by moving, thus movement is a topic that should be studied in cosmology. More precisely, he continues, the topic of movement can be approached with three questions: what is movement, how it can be measured and what laws govern it. Of these three, Crusius explains, the first one is clearly cosmological, while the second one was dealt in ontology. The third one, Crusius concludes, is partially cosmological, because some laws of movement can be deduced from the very essence of movement, although some laws of movement must be proven empirically and thus belong to physics.

Crusius then defines movement as a state of a substance that changes its place. Its opposite is rest or a state where a thing does not change its place. Crusius notes also that some movement is only apparent, when a thing does not change its absolute place, but only its place in relation to some other thing. True change, where a thing changes its absolute place, he further divides into external change, where the whole thing is moving, and internal change, where some actual parts of a thing change their places so that their positions in relation to other parts of the whole are changed. Crusius points out that these two classes are not mutually exclusive, since there can occur situations where a thing moves, while its parts change their place in relation to one another.

What then could move in these different ways? Crusius notes that a simple substance cannot at least move internally, since it doesn’t have any actual parts. Then again, infinite things (or from Crusius’ perspective, God) cannot move externally, because there is nowhere where such an infinite thing could move as a whole. Furthermore, he adds, everything that is finite, can move at least externally, whether it is simple or complex.

Crusius divides external movement into total external movement, where the whole substance moves completely from one location to another, and partial external movement, where actual or ideal parts of the thing change their place: once again, the two classes are not mutually exclusive. While the notion of total external movement seems clear enough, it might be difficult to see how partial external movement differs from internal movement. One example of a partial external movement that is not internal nor total, Crusius says, is such where a simple substance grows and thus its ideal parts change their places, since this involves no change of actual, distinct parts of the substance. Another example would be rotation of a sphere: the sphere as a whole does not go from one location to another and the relative positions of its parts remain the same, but the parts of the sphere do change their absolute positions.

Crusius derives some simple consequences from his definition of movement. Movement, as he sees it, has always a definite direction, and indeed, a start and end point. It also has certain characteristics: velocity and strength by which it withstands resistance. Furthermore, Crusius notes that movement of a complex substance is defined by the movement of its parts.

Movement, Crusius emphasises, is a positive change and thus requires a positive cause. Rest, on the other hand, is for Crusius just a lack of movement and does not therefore require any cause. In other words, a thing rests, Crusius says, if it has no reason to move, and if the cause of the movement vanishes, the movement must also cease. A direct consequence of this is that increase in the velocity of movement requires a similar increase in the cause of the movement. Crusius also thinks that change of the direction of the movement must also have a cause, which would make the Epicurean idea of atoms swerving without a reason ridiculous.

Because motion always requires some cause, Crusius continues, state of movement cannot be indifferent to the matter. By this Crusius means that a moving cause has to at first overcome an inherent resistance in moving a piece of matter. This inherent resistance is, of course, inertia. More precisely, Crusius calls it metaphysical inertia, distinguishing it from physical inertia, where the resistance is not just an inherent property of matter, but also involves a force, although one that is, as it were, dead, that is, suppressed by the moving force. Beyond inertia, motion can be resisted also by a living force, that is, a force that truly can resist the moving cause.

Crusius notes that a finite cause of movement cannot really affect a thing more than the thing resists the movement. Of course, the cause can have more force, but it only uses as much force as is required for overcoming the resistance. Thus, Crusius thinks he has justified the law of action being equal to reaction. Although a non-empirical proof, Crusius clarifies, we still require empirical observations to determine how much a finite cause acts at a given situation.

It is an essential feature of substances that differ from God, Crusius says, that they cannot penetrate one another. Thus, when a finite substance, whether matter or spirit, tries to occupy the same place as another finite substance, it will drive away the other substance, that is, pushes it. Crusius adds that pushing is just an existential effect, in other words, it doesn’t require any force, but the mere presence of one substance trying to occupy the place of the other.

Pushing a substance makes it move: Crusius calls this a communicated movement. Indeed, he says, communicating movement is the only way finite substances can affect one another. Series of communicated movements cannot go on forever, he immediately adds, and such series cannot all derive from God’s miracles, because that would be against the purpose of the world. Thus, Crusius argues, there must be some finite substances that can move their own substance through their inner activity - such movement he calls original. The inner activity causing original movement can be constant or conditional striving, inherent to some elements of material things, or it can be free willing. Because even the activity of elements is ultimately derived from God, Crusius concludes, all movement is generated by some spiritual activity that is not movement.

Communicated movement, Crusius notes, need not always be just an effect of the impenetrability of finite substances, but can also involve an inner activity of a substance. He is thus against the Cartesian idea that interactions of material things would have to be explained solely through geometric properties: God can give material things some inner activities. Crusius faces the possible objection that such activities are what were disparagingly called occult qualities by noting that we can know such activities as well as finite creatures can, when we can distinguish them from one another and deduce their existence from their effects.

Crusius progresses then to describe several rules involved in the communication of movement, such as parallelogram rule and behaviour of elastic substances. I will not follow him to these details, but I shall take a look at a few conundrums concerning movement that Crusius considers. First of these involves the question of the quantity of movement in the world: is it always constant? Crusius’ answer clearly has to be negative, because this would preclude the possibility of spirits to interact with the world. He even denies the weaker assumption that the world would have a constant amount of moving force, because spirits should be able to choose how strongly they move other things.

Another conundrum concerns the question whether all the matter in the world is moving constantly. A reason for upholding such an opinion would be that a constant movement is required for explaining why shapes of things remain stable: without the constant movement of the surrounding matter, a thing could just change willy-nilly its shape. Crusius does not find this argument convincing. The shape of a complex thing is determined by the shape and position of its parts, while the shape of a simple thing is either chosen by God, with or without any reason, or caused by themselves or by external forces - where is the need for movement here?

The answer to the question, Crusius concludes, belongs to physical, not metaphysical cosmology. He does state that the ultimate limits of the world cannot move and similarly all things that God has determined to rest. Other things, then, probably at least strive to move, whether through their own inherent activity or through being spurred to movement by things outside them.

Finally, Crusius ponders the question whether movement of one material thing necessarily sets all other material things in motion. He notes that if the world contains spaces void of any finite things, movement of one thing could go through this void without communicating movement to other things. Furthermore, he continues, even if there is no void, certain material things could also just switch places without affecting other material things.

Crusius also thinks that these arguments disprove the idea endorsed often by Wolffians that from state of any substance in the world could be determined the state of all other substances. This proposition of Wolffians was explicitly based on the supposed continuous causal nexus of all the parts of the world, where movement of one piece would eventually affect all the other pieces. If this nexus fails, as Crusius deems very possible, the states of the substances in the world would not be as closely interlinked, although they would be really connected.

Christian August Crusius: Draft of necessary truths of reason, in so far as they are set opposite to contingent ones - The essence of the world

After going through what can be known about God, Crusius continues with the question of the world. His aim is to do metaphysical cosmology, that is, to describe what any world in general must be like and what we can know about this necessary essence of worlds without any help of prior experience. Thus, metaphysical cosmology in Crusius’ sense is not a physical endeavour and does not aim to describe our actual world.

Crusius faces the problem that since we do not even know our actual world completely and certainly don’t know what all the possible worlds are like, it seems impossible for us to know what worlds would necessarily be like. He admits that metaphysical cosmology must be incomplete. Firstly, he says, only God could know all the possible characteristics a world could have. Secondly, we are unsure even of many features of the actual world whether they are necessary: for instance, should every possible world have colours?

Despite these misgivings, Crusius thinks that we can still know some important truths of metaphysical cosmology. Firstly, all possible worlds are also things and thus must have characteristics that ontology has shown all things to have. Secondly, natural theology also implies things in cosmology, because any world would be God’s creation and would thus reflect their essential properties. Finally, he concludes, the very concept of the world must imply what a world must be like.

Furthermore, Crusius notes that we do not need to observe different possible worlds in order to form a distinct concept of a world - we just have to be able to distinguish a world from anything that is not a world. Firstly, Crusius distinguishes the world from God: the latter is necessary, the former is not. Secondly, a world is not an individual creature, but a sum of creatures, although, Crusius admits, God could have created just a single creature.

Not all collections of creatures are worlds, Crusius emphasises. Some collections are just connected by the observer, but a world should truly be a unity, not just in someone’s thoughts. Finally, Crusius notes, a world should be a real whole, not a part of something larger. Crusius’ final concept of the world is then that world is a real combination of finite things that is not again a part of another, to which it would belong through a real combination.

As a combination of things, Crusius says, every possible world must be spatial. In addition, because a world is particularly a combination of finite things, it must necessarily be of finite size. Crusius is especially keen to point out that although mathematics speaks of infinite spaces, this is just an abstract fiction that is not truly possible in a world. God, on the other hand, should exist wherever the world is, but God is not limited by the limits of the world. Crusius also accepts the possibility of world having void spaces in it - that is, spaces void of finite creatures, because God would exist even within void.

In addition to being spatial, Crusius continues, a world must also be temporal. He adds that because a world is created by God, it must have not existed at some point in time. World also could not exist by itself, even after creation, but must be sustained by God. Crusius appears to assume that God does not create anything else in the world after the first creation, but he does admit the possibility that some part of the world might have been isolated from another part for a while, while the two parts would later come in contact with one another. Thus, he suggests, the physical law of the constant quantity of forces is not as such necessary, because we cannot be sure that the world does not contain such isolated, unknown forces.

Crusius also emphasises that God has created the world for some purpose. As he has pointed out earlier, the purpose of creation has to serve especially the free creatures with the ability to reason. Thus, other things in the world must be either means for that purpose or then necessary consequences of creating and arranging the world to serve the purpose. Whatever the purpose of a particular possible world is, the world must be good, because its creator is also. Then again, no world can really be the best possible world, because all worlds are somehow imperfect and could be improved.

An interesting question Crusius considers is what belongs to an identity of a world: how much a world can be changed before it becomes a different world? Obviously, one could take the primary constituents of a world - simple substances - and reorder them in a different manner. Yet, this answer concerns only the ultimate metaphysical subject of what makes a world and ignores the intriguing problem of whether a world has some inherent structure that differentiates it from any other world made out of the same substances.

Crusius outlines next his criterion of a world’s identity: a world remains same, as long as it still serves its fundamental purpose and in particular no individual things, their combinations, laws governing them and their essential actions change in a manner that would change this inherent purpose or any means required for the fulfilment of that purpose. Any change that does not do this, he continues, merely changes the state of this world. Indeed, he points out an important type of change that does not change the identity of a world. A world is created for the sake of free creatures and for enabling their free actions. Thus, he suggests, whatever persons do freely should not affect the essence of the world they inhabit, because that would mean the very purpose of a world could contradict itself.

Because things in the world are combined, Crusius insists, they must be able to interact with one another. In these interactions some things must be active or affect one another, but Crusius notes that there can be passive things that do not have any force to affect other things, but at most enable something through their existence. Both active forces and inactive abilities can combine things into more complex wholes.

Furthermore, Crusius continues, interactions that combine things are governed by physical laws that should hold independently of our thinking of them. Crusius notes that there are also laws of understanding that merely say what propositions follow or are possible in certain circumstances, but these differ from real physical laws. Similarly, he distinguishes physical laws from moral laws, which say what should be done according to commands of some lord.

Now Crucius defines nature as the sum of all substances in the world, together with the physical laws governing their combinations. Natural is then something that happens through the fundamental forces of created substances, while God does nothing else, but sustains these substances and fundamental forces. Supernatural, on the other hand, is something caused immediately by God. Because at least the sustainment of the substances and their fundamental forces is an immediate effect of God’s action, Crusius concludes that every world has something supernatural in it.

Crusius thinks that we can conceive no other interaction between finite things than interaction through movement. Since we are dealing with finities, he continues, we can invoke the principle that this non-conceivability reveals a true dependence relation: finite things can affect one another only through movement. Thus, when a finite substance affects another, it either forces the other to move by its own impenetrability or then its motion awakens some other activity in the other substance.

This other activity that can be awakened by motion, Crusius insists, is either thinking or willing, which we know are not movement. He then distinguishes two kinds of substances in the world: material substances, which can only move, and spiritual substances, which move, but also think and will things. Furthermore, he divides matter into two further subclasses: metaphysical or inactive matter that has only a passive capacity for movement and physical or active matter that has also some active force.

Crusius has noted that the world has been made for the sake of free spirits, thus, the world must, undoubtedly, have spirits in it. One important consequence of the existence of free spirits is that Crusius’ world cannot be completely deterministic. A world need not have matter, on the other hand, but matter can exist in it. Then again, Crusius notes, because everything in the world must somehow serve its purpose or free spirits, matter and spirits must be able to interact: why else would God have created it? Crucius brushes aside the old Cartesian worry that spirit could not affect matter, because they are two different types of substances: dogs and humans share characteristics and still are of different species. Crusius sees no problem in accepting that spirits are also impenetrable, like matter, and can thus move and be moved by material objects.

Crusius is unsure about the Leibnizian principle that there are no two things that cannot be distinguished from one another. He does admit that no two spirits can be completely similar, because everyone of them perceives the world from a somewhat different perspective and perceptions change their inner state. The case is different with material substances, Crusius says. The principle itself cannot be justified without experience, he insists and thinks that all supposed proofs of the principle have been sophisms: if God would have wanted, two different and still completely similar material substances could have been created. True, he admits, experience appears to show that seemingly similar things often differ in some manner. Yet, there is no assurance that at least some of the simplest parts of matter wouldn’t be completely similar. Still, Crusius suggests, God has probably created at least many different kinds of simple material substances, because this would provide more means for helping the world to fulfil its purpose.

Whatever the ultimate elements of matter are like, they can be combined into more complex substances or bodies. Indeed, Crusius says, matter as a whole probably has to be dispersed into distinct bodies, because this better helps to achieve the purpose of the world. Crusius distinguishes physical from mathematical bodies, which are mere possible divisions of space. Physical bodies, instead, are not united just because we think of them as united, but through something real that separates them from other bodies. Crusius suggests three kinds of such unifications. Firstly, parts of a body can be held together by inactive, unmoving substances surrounding it. Secondly, parts of a body can be held together by moving substances surrounding it, such as the vortexes in Cartesian physics. Finally, parts of a body can be held together by an elastic matter, that is, matter that has an innate tendency to return to a certain shape.

No other ways to unite material things into bodies exist, Crusius insists. He is especially keen to deny any attractive or cohesive forces that would hold parts of a body together, because all explanations why material things stay together should be reducible to fundamental forces. Cohesive force cannot be a fundamental force, he adds, because cohesion is just another name for material parts staying together and so merely describes the phenomenon without explaining it. Then again, Crusius denies the existence of attractive force, because such an action in distance breaks the requirements of what a force and causal interaction should be like. Finally, Crusius also denies that parts of bodies would stay together because of common feeling, since feeling is something he allows only spirits to have.

However the bodies are held together, they then interact with one another and with the spirits. Despite the interaction between the two types of substances, Crusius notes, these different classes can also be regarded in abstraction from one another. Thus, spirits of the world, in separation from material things, form a spiritual world, while matter as such forms a material world, and when regarded as separated into distinct bodies, a bodily world.

The bodily world particularly, Crusius says, can be seen as a machine - that is, as a body of its own, combined from parts that are shaped for some purposes in such a manner that these purposes can be actualised with the aid of the shape and the position of these parts. This is not true, he adds, of the whole world, because this also includes spirits that cannot be parts of a body. Furthermore, he notes, although the bodily world is a machine, all its parts are not, for instance, a stone is just a body, but not a machine. Finally, Crusius points out that the bodily world is a rather peculiar machine, because part of its driving force comes from actions of free spirits.

Although spirits are not machines, they can be combined with naturally produced machines. Crusius is obviously speaking of organic bodies, combined to which spirits are called souls. Crusius suggests that it is not completely necessary that worlds contain animals or combinations of souls and organic bodies. Animals do make a world more perfect, but finite spirits should be able to affect the bodily world even without the help of a body of their own.

For Crusius, the world is not a deterministic whole, because it also contains spirits capable of free actions. God’s interactions with the world provide further reasons why determinism does not work. We’ve already seen Crusius to note that God has a constant supernatural effect on the world, for instance, in sustaining the world and all the substances in it. In addition to such constant effects, Crusius also thinks that God can occasionally have quite sudden effects on the world, that is, God might do miracles.

Some of the miracles can be hidden from us humans - they are done merely, because God thought it best to do things in such a manner. At other times, God might choose to reveal that a miracle has been done - in these cases, Crusius adds, God must want humans to know that some event was a miracle. Sometimes the miracle might appear to be a work of a person following God, but even in these cases it is God who actually gives the person a power for doing such miracles. In these cases, Crusius explains, it is futile to try to make experiments whether this person truly can consistently make miracles, because God can at any point just choose not to grant that power to the person anymore.

How then to know when some event has been a miracle? Crusius points out that because of the possibility of hidden miracles, we can never be sure that something hasn’t been a miracle. Yet, he also gives a general criteria for recognising miracles: something is a miracle, if it could not have happened in a natural manner generally or at least in these specific conditions. He also adds that we are sometimes very able to distinguish supernatural from natural events, because we are so familiar with what naturally happens: for instance, we know trees don’t usually talk. Crusius also points out that we do not need mathematically certain proofs to accept something as a miracle, but a lower grade of conviction is usually enough. Finally, he emphasises that miracles also have a moral aspect, that is, we shouldn’t think of something with immoral consequences as a miracle.

Christian August Crusius: Draft of necessary truths of reason, in so far as they are set opposite to contingent ones - Good and perfect

Crusius concludes his study of ontology with the notions of perfection and goodness. He is especially eager to reject the Wolffian notion of perfection as a harmonious unification of a manifold. Instead, he suggests, by perfection we can, firstly, mean the sum of positive reality ascribed to a thing. He clarifies the definition by noting that this positive reality refers to the causal powers of the thing or effects that become possible or actual through it. Secondly, Crusius adds, perfection can also mean an individual aspect of the thing contributing to this sum of positive reality.

Just like causal power, Crusius notes, perfection can also be either infinite or finite, and in case of finite perfections, there are always higher and lower levels of perfection. In a sense, any perfection beyond the infinite is lacking something, but even finite things can be perfect in their kind, Crusius assures. Furthermore, he adds, perfection can be either essential, that is, presupposed in the essence of a thing, or contingent, that is, aspects increasing the perfection of the thing, but not presupposed by its essence. It is the essential perfections that make a thing perfect in its kind, while contingent perfections by themselves cannot do this - a mirror that reflects poorly is an imperfect mirror, no matter how costly frames it has.

How then to decide what belongs to an essence of a thing, and consequently, to its essential perfection? Crusius says it all comes down to purposes they are made for. In case of things generated by natural causes, he notes, we might not be able to say what the original purpose of the creator was for them. In this case, we can try to determine their purpose and thus their perfection from what we have experienced of them and their parts.

Just like with many concepts earlier, Crusius notes that perfection can be either ideal or real. By ideal perfection he means a property of a thing, by which understanding can perceive more truth, order and relations in it. He especially considers the notion of order, that is, an arrangement of things in a manner that appears to have been done according to an idea or a model. Depending on the model, order can be better or worse, but generally, Crusius says, it is better the more diverse things are arranged harmoniously. Order can be based on similarity, but not necessarily, for instance, letters of very different sort are ordered in words.

Real perfection, on the other hand, makes possible something else than mere knowledge of order. In other words, real perfection is for Crusius either an active cause generating something actual or an existential ground making something possible or determining something.

In addition to the division of real and ideal perfections, Crusius also mentions a division into external and internal perfection. Here, external perfection means something we can sense, while an internal perfection is to be found in an inner essence of a thing. Interestingly, Crusius notes that a thing that is externally and internally perfect is by definition beautiful.

Crusius lists various signs that something can be taken as perfection. For instance, any part of an essence can be taken as perfection, thus, understanding is a perfection. Furthermore, anything serving purposeful sustainment of the essence is perfection, like health, as is anything that makes a thing capable of securing more of its purposes or surer or easier to do so, such as prudence or science. Perfections include also anything that forms a main purpose of a thing or is a required means for it, such as virtue and care for one’s well being. Finally, the class of perfection contains anything that is an unavoidable consequence of a perfection, such as despising unfounded gossip, and also anything showing perfection, like art.

Not all that seems perfect truly is so and vice versa, Crusius clarifies. For instance, looking at mere ideal and external perfections, such as beautiful book covers, might confuse us to think that the thing in its essence is also perfect, when it is not. On the other hand, what is imperfect from a partial perspective could be perfect from a larger perspective, for instance, if the main purpose of the thing requires such a partial imperfection. Thus, while lack of light is usually an imperfection in a room, it is not, if the room in question is cellar.

Crusius ponders the question whether perfection belongs to things necessarily. Since the infinite substance has only necessary properties, its perfection should also be clearly necessary. Crusius also insists that all the things dependent only on the choice of the infinite substance must be perfect in their own kind. This still leaves the cases where free choices of finite substances are involved, and it is this freedom that brings about the possibility of imperfection.

From perfection Crusius turns to the notions of purpose - what a person wants - and means - what a person uses to achieve a purpose. A purpose is good, Crusius says, if it agrees with the essential volitions of the person, while a means is good, if it agrees with the purpose it should serve. The latter notion of agreement, particularly, has many different subtypes: a true means really helps to obtain the purpose, a certain means generates it always or regularly, a sufficient means can do it without any other help and a strong means generates the purpose exceptionally well or for a long period of time or for many persons.

Goodness is then for Crusius a concept necessarily linked with the concept of a purpose, but different notions of goodness arise depending on whose will the purpose is supposed to depend on. Thus, a finite thing is metaphysically good, if it corresponds to a purpose set by God on the natural chains of events, and physically good, if it corresponds to volition of finite persons. These two types of goodness can be defined also in terms of perfection, Crusius adds, because e.g. a thing is physically good if it makes some person more perfect. Still, all varieties of goodness cannot be reduced to perfection, Crusius notes and refers especially to a notion of moral goodness, which is especially a property of free persons and their actions: the condition of a person is morally good, if it agrees with the law willed by the infinite substance.

Finite things can be good, but the infinite substance must be good, Crusius emphasises. Indeed, the infinite substance is good in many ways. It is essentially good, because it is the only possible source of goodness for finite things. Then again, it is also good as showing kindness toward finite things. In addition, the infinite substance is also good also without any regard to finite things, because it is constantly what it can be.

Just like goodness, evil comes also in many varieties, Crusius says. A thing can be physically evil, if it is in conflict with desires of a finite person. Secondly, a state of a person can be morally evil, if it contradicts the divine law. Finally, a thing can be metaphysically evil, if it is not fit for achieving those effects, which should be possible through it according to divine purposes. Crusius notes that things depending on mere natural chain of events cannot be metaphysically evil. Thus, metaphysical evil always requires the intrusion of a free choice and is thus a species of moral evil.

Christian August Crusius: Draft of necessary truths of reason, in so far as they are set opposite to contingent ones - Finite and infinite

A key pair of ontological concepts in traditional metaphysics has been that of infinity and finity, thus, it is no wonder Crusius investigates them also. Simply put, finite is that which has limits, while infinite is that which has no limits. These definitions leave it still unclear what having limits actually means. Crusius explains that limit means an end to that where thing is thought, that is, something where the essence of the thing cannot continue to a higher grade, cannot spread into larger space or cannot have a longer duration. This definition implies, Crusius says, that a limited or finite thing can be multiplied in grade, space or duration, in other words, something greater than it can be thought.

Infinite in some aspects, on the other hand, is such that greater of it cannot be thought. Crusius continues that there are then three types of infinity, as there are three aspects involved with every existing substance. Firstly, every substance has an essence, which is ultimately based on its fundamental forces: here, infinity means that a substance is capable of all possible actions. Secondly, in addition to essence, substances exist in space and time, both of which have their own types of infinity: immeasurability, where a substance occupies all possible spaces, and eternity, where the duration of a substance has no beginning or end.

Crusius also notes that none of the three types of infinity should be confused with what could be called infinity of progression, which is no true infinity, but a mere series of ever greater things, which still always remains finite. For instance, a thing generated at some point of time could continue existing without any end and still its duration would always have been just finite. Crusius suggests that such an infinity of progression is the only way we humans can think also the infinity of the past: we set out a past moment, then a still further past moment etc.

Interestingly, while Hoffmann rejected the so-called ontological - or as he called it, Cartesian - proof of God’s existence, Crusius appears to accept it. He starts with the notion of a substance with an infinite essence, that is, with capacity to do anything - such a substance has then an infinite grade of perfection. Now, Crusius continues, if a substance should be capable of everything, it should be capable of ensuring its own existence, or existence belongs to the perfection of the infinite essence. This means, he concludes, that a substance with infinite essence must necessarily exist everywhere and at every time.

Crusius argued earlier that necessary things can only be simple - otherwise they could be broken - and this must then apply also to an infinite substance. Its simplicity then implies that an infinite substance cannot be reduced. In fact, he points out, there can be no quantitative relation between the infinite substance and finite substances. In fact, nothing could be added to a finite substance to make it infinite, and finite and infinite substances differ by their essence.

Crusius makes the remark that one might think as an infinite force a determined capacity for doing a certain type of action in as great a magnitude as possible. Force of an infinite substance is not of this sort, he clarifies, but a general capacity to do anything whatsoever, even what any of these determined infinite forces could do. Indeed, an infinite substance should have only one force, which it can then apply in different manners. Of course, Crusius admits, the infinite substance cannot do anything impossible, but this is more of a clarification than any real limitation. The infinite substance does not then need any instruments for its actions, but if it so chooses, it can use them. In fact, since no effect of the actions of the infinite substance could be the highest possible, it can freely choose the magnitude of its effects.

Infinite substance should be able to do anything that just is possible. Crusius argues that creation of all finite simple substances is one of the things the infinite substance has done. True, he admits, it is inconceivable to us mere humans how an infinite substance has done this, but as contingent they must have been created by something, and since a finite mind cannot apprehend an infinite substance, it is understandable that we cannot fathom everything it could do. Crusius notes that there is also nothing contradictory in finite substances creating finite simple substances, although it is again inconceivable how they could have done it. Still, he assures the reader, we should not assume any finite substance to have such a power, because this assumption would undermine our ability to investigate natural causality, which is based on the premiss that finite substances can only bring about something by combining existing substances or by dividing existing combinations.

Crusius also considers the question, whether there could exist at the same time an infinite amount of things. His first point is that we certainly can always think of a number greater than any given number, thus, we shouldn’t be able to think any infinite number (of course, nowadays mathematicians do think of infinite numbers or cardinalities, but since they also form a never ending series of infinities, these would not actually be infinite in the sense Crusius means; still, this is a distinction that we can ignore when speaking of what Crusius had in mind).

Now, although we cannot think of an infinite number, this might not imply anything for the possibility of an infinite amount of real things. Here the crucial question is, Crusius suggests, whether this infinite amount is meant to be added up from actually different, perfect things. If it is, Crusius insists, we should be able to divide this amount into two groups. Since neither subgroup is the greatest, they are both of a finite amount, but then an infinity would be made up of two finities, which contradicts the idea that an infinity cannot be quantitatively compared with something finite.

Then again, Crusius notes, the previous argument works only if it is really distinct things that are added up and divided into groups. Thus, God might be able to think at once an infinite amount of possible things, since these possible things are not really distinct. We finite beings cannot comprehend how God can do it, but this does not restrict God’s capacities.

A far simpler question, Crusius thinks, is that of an infinite series of causes and effects, because Crusius smells a contradiction in that notion. In a series of causes and effects, he argues, all terms are either generated or not. If not, the series has a first cause and is therefore finite. Then again, if they all are generated, then the individual members have all not existed at some point and therefore the whole series has not existed at some point and has thus a beginning. Key part of this argument is clearly the move from all parts of a whole to the whole itself. Crusius notes that this move does not work in all cases - if parts of a whole weigh 1 kg, then the whole will definitely not weigh 1 kg. He unconvincingly tries to argue that usually and in this particular case this move is guaranteed by a principle of non-contradiction, because whole just is parts taken together.

Whatever the validity of the argument, Crusius believes he has shown that a series of causes and effects cannot be really infinite. He does admit it can have an infinity of progression, that is, it could have more members. These members could also be added to the beginning of the series, that is, we could think that the series began from an earlier point than it does, but this just means that it is completely arbitrary where such a series begins.

Because all series of causes and effects are thus finite, Crusius says, the essence of an infinite substance cannot consist of such a series of changes. Even more, he insists, the infinite substance cannot go through any series of changes, because it would undermine its eternal perfection. Crusius might be arguing here against the idea that God could be persuaded by a series of reasons to do something. In any case, he notes that an infinite substance should be immediately everything it can be.

The lack of changes in the infinite substance means according to Crusius, firstly, that all the actions of the infinite substance must be fundamental, free actions. Secondly, the infinite substance cannot be affected by a finite substance, at least not directly. Crusius does admit that finite substance could hinder actions of the infinite substance by not fulfilling certain conditions the infinite substance has placed for its own action. Furthermore, finite substance could resist finite effects generated by the infinite substance.

Although Crusius speaks against the idea of an infinite series of causes and effects, his attitude toward an infinite duration is quite the opposite. Indeed, he is committed to the idea that the first, uncaused cause has existed an infinite amount of time or eternally. One might argue that Crusius’ commitment should fall to the very same argument he himself used against the infinite series of causes and effects, creating then a dilemma reminiscent of Kant’s third antinomy, where we cannot accept either that there is an uncaused cause nor that there isn’t. Crusius’ solution is once again to differentiate between actual and merely possible. A series of causes and effects involves an actual succession of things, while an infinite duration consists only of possible succession of things, whereas nothing really changes during the existence of an eternal substance.

Christian August Crusius: Draft of necessary truths of reason, in so far as they are set opposite to contingent ones - Simple and complex

Concepts of simple and complex substances were of great interest to Wolffians, being one of the primary divisions of substances, and Crusius seems eager to show where Wolffians wen’t wrong with them. He firstly notes that just like the concepts of part and whole, on which the two former concepts are based on, can actually mean very different things. Starting with the parts, these can mean, Crusius says, any group of things we can represent as forming also a one thing, which then is the respective whole. Furthermore, these parts can be actual or such that they can be separated elsewhere than in our thoughts, but they can also be mere thought parts, which can be distinguished in our thinking, but not really separated.

Simple is then for Crusius something that has no parts - in some sense, while complex is something that has parts - again, in some sense. Since the notion of parts was already twofold, this same duality continues with the notions of simple and complex: something may be simple or complex just based on mere thoughts, but also based on something outside our thought.

Even in case of actual simplicity, Crusius notes, there are various levels of simplicity. The epitome of simplicity, he thinks, is God, who is not just a simple substance - that is, something, which cannot be separated into further substances - but also has a simple essence in the sense that no property could be removed from his essence. This is not always the case, Crusius says, because substance can be simple, like a human soul, without having a simple essence. Even a complex substance, like air, Crusius notes, is simpler than, say, a human body, because the former has only integral parts - parts that all have the same essence - but no physical parts - parts that have a different essence from one another.

Crusius also notes that it is a different thing, if something is simple as such or has nothing separable in it, than if something is simple on the condition that the current world exists, Crusius notes that we cannot really distinguish between the two cases and neither can any finite being, but God might be able to do it.

Every force is in some subject, Crusius insists, because no subjectless forces could be thought of. On this basis Crusius argues that in case of complex substances, their force must be determined by forces of their parts. Crusius then concludes that if a complex substance wouldn’t ultimately consist of simple substances, the constituent forces would have no immediate subject where to subsist, which he thinks is absurd. Despite the seeming complexity of the argument, it appears to just assume what it sets out to prove: that the existence of a complex thing must be based on the existence of simple things.

Crusius is especially keen to distance his notion of a simple substance from a mathematical understanding of simplicity. Mathematics, he says, considers only abstract magnitudes, not other determinations of things. In other words, he rephrases, mathematics is only about the concept of space and its possible divisions. Thus, it was natural for mathematicians to assume the existence of points, which should have even no parts that could be thought of as being outside one another. Yet, Crusius states, no true simple substance is simple in the mathematical sense, but is spatial - they just cannot be physically divided further.

Crusius goes thus straight against the Wolffian notion of elements, which are more like non-spatial forces. If we would accept such non-spatial substances, how could we account for spatial matter being generated from them, especially as any concrete matter would require an infinite amount of them? Furthermore, he continues, we couldn’t even say how such pointlike substances could touch one another, as there are always further points between any two points.

Christian August Crusius: Draft of necessary truths of reason, in so far as they are set opposite to contingent ones - One and the same

From the very start of metaphysics, in the book with that name by Aristotle, the concept of one was regarded as an important topic. Thus, it is no wonder that Crusius would consider it. Indeed, he thinks that we have many different notions of one, distinguished by what concepts they are opposed to. First of these is the concept of one thing in contrast to several things. This concept, he insists, cannot really be defined, but can only be exemplified. In essence, a thing, no matter what it is, is always one or a unit, because we can think what it would be like, if it were multiplied into several similar things.

Another concept of one, Crusius continues is that of something unified in contrast to what is disunified. By unification Crusius means a relation where things are so intrinsically related under certain conditions that when one is assumed to exist, the other must be assumed to exist also. Unification can come in many forms, the primary ones of which are unification merely in our thoughts and unification in real existence. Crusius notes that we cannot really know all the subdivisions of unification and mentions only a few examples, such as metaphysical unification of one thing subsisting in another (e.g. property in a substance), existential unification of two perfect things connected so as to become inseparable, such as a hand and a torso, and moral unification where two persons are united by having common goals. In any case, Crusius emphasises, all cases of real existential unification are ultimately based on causal interactions. Thus, he insists that Leibnizian pre-established harmony would be no real unification of body and soul.

A third notion of one is connected with the notion of identity. Crusius defines the concept of identity as the opposite of difference, where two things are different if in one is something that is not in the other - Crusius notes in passing that this notion of “not” or denial is again something simple, which we cannot really define. Identity as the denial of difference can then be just similarity, where things share something, but also identity in a strict sense, where one thing - here is the connection to one - is represented through two concepts, of which one is found to contain nothing that wouldn’t be contained in the other.

Crusius considers the question, when we can know that the objects of two concepts are identical. The criterion he suggests is that one should be able to replace what is thought in one concept with what is thought in the other without any consequence. He also emphasises that mere same essence is no true criterion of identity, since we could have substances that are just numerically different, that is, that would agree in their absolute properties, but would be e.g. in different spaces at the same time.

Although Crusius' definition of identity might seem rather rigid, he does admit that identity can fluctuate according to the viewpoint chosen. For instance, when we are considering whether things at different points of time are the same thing, we might get different results depending on what we focus on: corpse is in a sense different from a living body – they have different essence - but in another sense they can be identical, because they share the same matter. Then again, if an essence of a thing consists of a certain relations of parts, the thing can remain identical, despite its parts being replaced by different, but similar parts.

Crusius chooses at this point to give a list of simplest concepts. This list is a development of a similar one from Hoffmann, and we could consider it to be a precursor of Kant’s list of categories. Crusius' list contains the following concepts:

• Subsistence, that is, the relation between a property and its subject
• Relation of one thing being spatially within or outside of another thing
• Succession
• Causality
• Relation of one thing being figuratively outside of another thing, in the sense of not being its part, property or determination
• Oneness in opposition to plurality
• Relation of things being unified
• Thing’s being somewhere in space.

Crusius also clarifies further the relation of these simple concepts to the seemingly simple concepts of sensation, like colours. Crusius’ idea is that while the above mentioned simple concepts are the ultimate result of analysing more complex concepts for any understanding, it is we humans who are incapable of analysing sensations just because they are caused by unknown activities affecting us in a confused manner, so that we cannot distinguish these causes from one another. Crusius also distinguishes the simple concepts from indeterminate, symbolic concepts, which we cannot really think, but which we can only represent by saying what it is not and what its relations to other things are.

Christian August Crusius: Draft of necessary truths of reason, in so far as they are set opposite to contingent ones - Space and time

Crusius begins a new chapter by pointing out that our thinking begins from sensations. This implies that we already implicitly begin with a notion of existence, sensation being its criterion. Crusius admits this, but adds that we must still abstract the notion of existence from our sensations.

We have seen Wolff defining existence as something added to possibility - in effect, this was no real definition of existence, but existence was a combination of various concepts, namely the existences of complex things, simple things and God, some of which we can define and understand, while others we can’t. Crusius does admit Wolff’s point in some sense. What Wolff was trying to do was to define existence in terms of how it is generated (for instance, complex things are generated by combining simpler things), and Crusius accepts that we cannot ultimately know where existence comes from. Yet, he insists that this is a false way to approach the problem and says that we can define existence rather simply as being in space and time.

What then are these space and time for Crucius? Starting from space, he says that space is just where we think all existing substances are and what is left, when we remove all substances in our thought. Space is then independent of all substances in it or absolute.

Crusius defends his notion of space with an argument that clearly inspired Kant’s discussion of space, although the conclusions of both are very different. Indeed, Crusius begins by pointing out that space is not considered to be a substance, since otherwise we would fall into an infinite loop, because all substances are thought to be in space. Then, just like Kant, Crusius considers the possibility that space might be taken as a property of some substance, but decides against it, because space is not thought to be in some subjects, but subjects are thought to be in space.

Finally, Crusius looks upon the idea that space might be a relation. He notes that if space would be a relation, it would have to be a relation of substances being next to one another (here the inclusion of the notion of a substance in the definition is necessary, because e.g. music also has things next to one another, namely, sounds, but space is the only thing, where these beings next to one another are substances). Still, Crusius concludes, even this possibility is unsatisfactory, because even a single substance would have to be thought of as being in space.

Crusius’ argument is meant to show that his notion of space agrees with what everyone thinks space is. There’s still the possibility that space is a kind of collective delusion or mere imagination. Crusius rejects this possibility by referring back to his criteria of truth: since we cannot separate in our thoughts existence from space, they should be accepted as truly connected, unless this incapacity of separation is somehow connected to limitations of our understanding. Kant would later argue that we really can’t say, if it is down to some limitation of our cognition, but Crusius does not consider this possible: otherwise, we would have to reject also the principle of sufficient reason as susceptible.

Crusius admits that some people have rejected the notion of absolute space as something independent of substances and taken it as a mere relation of substances. One reason for this is simply that they assume space must be substance, property or relation, and because the two first options seem impossible, they have assumed that it can only be a relation. Crusius notes that his very point has been that these are not all the options: while notions of substance and property are concepts linked to essences, spatiality is a component of or abstraction from concrete existence.

More concerning for Crusius seems the objection that the absolute space would rival God in dignity, because both would be eternal and necessary. Crusius’ answer is that space is not a complete thing or substance, but a mere abstraction from existence of all substances. Thus, even God is in a sense spatial, because he could be said to exist everywhere. Of course, Crusius thinks that God’s existence is not bodily and so cannot be sensed. Therefore space could be empty in the sense of being without any bodies, even with God present in it. Extrapolating from this, Crusius suggests that all simple substances might be in space in a similar non-sensuous fashion, or as he puts it in terms that Kant was to borrow later, they fill space, but do not extend it.

After defining some concepts related to space, such as location, Crusius turns to discuss time. His main point is similar as with space: time is not a substance nor a property or a relation, but an abstraction out of existence of actual things, and more precisely, their succession following one another. Importantly, Crusius thinks that time is absolute or independent of things and that it is not mere imagination. A point Crusius did not make with space is that although we cannot think of an infinity of time or eternity, this only tells of the limitations of our understanding.

Crusius then returns to the notion of possibility. He suggests that the criteria of possibility earlier considered - that of non-contradiction - delineates only the realm of ideal possibilities or possibilities in thought. A more substantial form of real possibility, he continues, refers to things that do not yet exist. In other words, such a real possibility will at some point come into existence, and its possibility outside thought is guaranteed by causes that will eventually make the possibility actual. Crusius notes that such real possibility is dependent on the existence of something, namely, its cause. Thus, if nothing exists, nothing will be possible.

When the realm of possible is restricted, the realm of impossible grows. Thus, not just contradictions make something impossible, Crusius explains, but anything that prevents something to have causes that would make them existent. Crusius refers especially to the principles he has inherited from Hoffmann that combination or separation of concepts we cannot make are impossible, barring the possibility that our incapacity is due just to our limited understanding.

We already saw earlier a few reasons why the principle should not hold, such as a revelation by some more perfect spirit. Here Crusius outlines a few further reasons, which he has again inherited from Hoffmann. Firstly, although we could not separate something from a negative concept, this might not be true of a more perfect being, for instance, although we cannot abstract things from limits, another being might be able to think infinities. Secondly, although we could not combine things, this might not be impossible, if we are dealing with immaterial entities.

Christian August Crusius: Draft of necessary truths of reason, in so far as they are set opposite to contingent ones - Thing is

Whether it was called something (Etwas) or thing (Ding), which Crusius prefers, ontologies of the time often began from a concept opposite to nothing. By this thing that is not nothing, Crusius explains, we can mean anything whatsoever that can be thought of. Yet, he continues, we can also distinguish in the class of things that can be thought those which we can only think (merely possible things) and those that are or exist also outside our thought (actual things or things in a more proper sense).

Crusius follows Hoffman in trying to find criteria for recognising what is possible and what is not and finding ultimately three criteria, only one of which is absolutely certain. The basic sign of something being a possible thing, Crusius insists, is whether someone can think it: possibility is thus equated with an ideal comprehensibility. Since no one could think as true such things that contradict themselves or known truths, we must assume that such contradictions are a sign of an impossible thing.

The principle of non-contradiction, Crusius says, is a demand that all possible things should fulfill. Then again, he adds, all possible things need not be comprehensible to us humans: a point that Hoffman made before Crusius. The idea behind this rejection is that a more perfect mind (such as God) might be able to comprehend something we cannot. Thus, if such a perfect and undeceiving person tells us to believe some apparent absurdity (say, about three persons in one divinity), then we should believe him. Crusius points out two other cases where we should believe such absurdities to be true or at least possible. Firstly, since the law of non-contradiction is the highest criteria of possibility, we must believe a seeming absurdity, if denying it would create contradictions. Secondly, if we are obligated to assume something incomprehensible in order to perfect ourselves, then we should surely accept these incomprehensibilities as true or at least possible. If none of these conditions holds and nothing else speaks to the contrary, then we should think it impossible to separate what we cannot think as separated and to combine what we cannot think as combined. These two principles complete Crusius’ criteria of possibility.

Moving on to Crusius’ criterion for recognising what is actual we might wonder whether he is actually talking about necessity: if we try to deny something actual, we immediately or mediately assume something we cannot think as true, that is, something impossible. The perplexity might go away, if we assume that, just like possibility was defined in relation to the perfect divine mind, so perhaps actuality is also here defined in relation to God. After all, God knows perfectly what there is, so if he assumes something to be non-existent, which actually is, he would land in contradiction.

Humans are not divine, so we have only a limited connection to what is actual. The human criteria of actuality, Crusius says, are always linked to sensation, which Crusius defines as a state where we are immediately forced to assume something without any further proof and which will not be revealed as imagination or dream when compared with other sensations. Indeed, without sensation we could not know that anything exists outside our own thoughts. Even our own existence we become aware of not through our thinking, like Descartes insisted, but through our internal sensation, Crusius concludes.

Having thus delineated the realm of possible and actual things, as far as we humans can know them, Crusius defines some further concepts that he will study in more detail later. For instance, when we think of a thing, whether possible or actual, we think it as distinct from other things. In other words, we think what this thing is as different from all others or we think about its (metaphysical) essence. This essence might be divided into various aspects, which help to distinguish the thing in question from some things, but not from others, just as redness serves to distinguish rose from green things, but not from tomatoes. Such aspects Crusius calls properties or qualities. Since what a thing is is a question different from whether a thing is, existence is still something different from essence and its constituent properties: essence and properties are something we can think of, existence is something beyond thought.

Christian August Crusius: Draft of necessary truths of reason, in so far as they are set opposite to contingent ones (1745)

It is interesting to notice that some central ideas of Crusius’ philosophy are based on the work of his teacher, Hoffman, who, for instance, invented the notion of thelematology or study of human will, the topic of the first book of Crusius we have studied. Crusius’ work Entwurf der notwendigen Vernunftwahrheiten, wiefern sie den zufälligen entgegengestellt werden also starts with a very Hoffmanian notion: metaphysics is a study of necessary truths, both of those which are necessary as such and those which are necessary, if we assume or posit the existence of a world. He does exclude some necessary truths from the realm of metaphysics: those of practical philosophy, where necessary and contingent truths are difficult to distinguish, and those of mathematics, which are simply too numerous.

Crusius’ definition might seem rather uninteresting: after all, Kant said that this had been the idea behind traditional metaphysics. Yet, once we look at e.g. Wolff, we see him defining metaphysics through certain topics and even including such disciplines as empirical psychology in it. Indeed, it seems more likely that Kant was accustomed to the way metaphysics was defined in Hoffmanian tradition - more specifically, he had read Crusius - and now just transmitted this idea further.

Although Crusius speaks against defining metaphysics through its topics, he does divide it in accordance with them. We are probably not surprised to find ontology and natural theology as parts of metaphysics, and by speaking of metaphysical cosmology, Crusius appears to just want to restrict the traditional discipline of cosmology to necessary truths and exclude e.g. laws of movement. A more unexpected name on the list is the so-called metaphysical pneumatology. It roughly plays the same role as psychology in Wolff’s metaphysics. Yet, unlike psychology, pneumatology is said to study only the necessary essence of spirits. What is especially missing is an account of the human soul and its relation to body, since it is not necessary that there are embodied spirits.

Although necessity is then an important feature of metaphysics for Crusius, this does not mean that he would want everything in it to be demonstrated. In other words, he distinguishes between necessity in an ontological sense from certainty. This means that even mere proofs of probability suffice, if demonstrations are not available. Indeed, Crusius adds, they might be even needed, when the demonstrations are available, because common people might not be prepared for the intricacies of complex demonstrations.

I shall still deal in this post with some general facts about the first part of metaphysics or ontology, leaving more precise details of Crusius’ ontology and the other parts of his metaphysics to further posts. The topic of ontology, for Crusius, is the most general features of all things. This means, he explains, that whatever things were given, a keen mind could discern the whole ontology from them. Indeed, he says more generally, whatever the topic of a metaphysical discipline, we could in principle discern everything of that discipline from an instance of that topic.

Ontology, Crusius explains, must then deal with the simplest concepts possible. This simplicity is not the same as simplicity in what we can sense, such as the simplicity of colours, which we can distinguish from one another without being able to explain their difference. Such sensuous simples are only simple, he adds, because we haven’t yet been able to analyse them further. The ontological simples, on the other hand, are the result of an analysis, and we know we cannot analyse them further. Still, we can distinguish even these ontological simples, because they play different roles in the analysis of complex things.

Next time, I shall begin a study of one of these simple concepts, namely, the notion of a thing.

Joachim Darjes: Elements of metaphysics 2 – The city of God

While the metaphysical compendiums in Wolffian tradition have usually ended with a look on natural theology, Darjes has left cosmology as the final chapter of his metaphysics. This makes some sort of sense, since he has already emphasised that cosmology is no proper part of metaphysics, since it does not deal with characteristics of all things or of things from one of the highest genera of things – cosmology is about world, which is a certain complex of things, consisting of many kinds of things (in Darjesian philosophy, material bodies and immaterial souls and spirits).

Another oddity is Darjes' inclusion of certain notions from natural law to his discussion. He is particularly interested of the concept of right and possession. Right to something, for Darjes, means that a person has the ability to use that something without hurting other persons or their rights. This seemingly innocuous definition allows Darjes to conclude that in fact God is the primary owner of everything – God surely can control everything that exists, and he cannot really hurt rights of others, since he made all things in the first place.

Darjesian definition has also important consequences for the rights of finite entities. Firstly, he notes that finite entities can really have rights only for complex things, because they have no power to do anything to simple entities. Secondly, since all things already belong to God originally, finite entities can have right to anything, only if God has provided them the right to use things in some manner.

In addition to owning everything, God also governs world. This means that he sets the goals toward which this ”city of God” strives. The main purpose divinity has set for everything, according to Darjes, is the happiness and perfection of all rational beings. Thus, Darjes concludes, all rational beings should strive for their own happiness and perfection and help others to find these also – and definitely not hinder others in their search.

Darjes does not go into particularities of what actions are good for happiness and perfection, but merely notes what tools God uses for guiding rational entities toward their appointed goal. Firstly, God can directly reveal some guidelines. Secondly, God might appoint further rewards and punishments and even a kind of heaven and hell, to provide further incitement for good actions. Despite these rather naive Christian notions, Darjes also supposes that all rational entities will eventually be able to perfect themselves – the purpose of punishments is also just to help personal perfection.

We are now finally finished with Darjesian metaphysics. Next up on the list is a return to the work of Martin Knutzen.