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

It is one thing to say that something is, another to say what it is. Thus, it is no wonder that Crusius considers the question on the attributes of God, in addition to attempting to prove their existence. Yet, he also has to at first argue that we can speak reasonably about God. After all, as he himself admits, God should be so far above all finite things that we cannot ever really comprehend their essence.

One common way to describe God is through metaphors taken from human life, for instance, when we say that God hears or sees all things. Crusius accepts such anthropopathies, assuming that they are not understood in a too literal manner that would imply God's finity - this would be anthropomorphism.

Yet, Crusius is also keen to find out more literal attributes of God, in order to alleviate all accusations of humanising God. He notes that anthropathies can still provide an inkling of such literal attributes, if one can just remove the metaphorical element from them.

In fact, Crusius adds, all things can provide hints of what God is like. Firstly one can concentrate on how things are perfect and then assume that God is eminently more perfect. Secondly, one can pay attention to the fact that God must be able to create everything in the world. Beyond these two roads, Crusius suggests we have only a third route of describing God - negative one.

Well, Crusius does admit also a fourth, that of revelation. He especially refers to the notion of God as a Trinity, which he considers as the closest we come to knowing God's essence - or at least knowing an attribute that is not either an infinitised attribute of finite things or a relation. Indeed, Trinity - that of being a substance composed of three individuals - is something completely unique to God.

The other, non-revelatory attributes of God Crusius divides into non-active and active attributes, depending on whether the attributes involve any action or a capacity to an action. Foremost of the non-active attributes is infinity. This means, Crusius says, that God cannot have any imperfections. Furthermore, it implies that God has majestity, that is, that he is infinitely removed from all finite beings and inconceivable to them.

Although Trinity, Crusius insists, God is still simple. That is, the three persons of Godhead are in themselves incomplete, although they can e.g. have different actions. Furthermore, the simplicity of God implies that God is not material and that human souls are not a part of God.

Crusius is also convinced of the uniqueness of God, although he is not satisfied with many of the proofs suggested for this position. For instance, Crusius does not think that one could prove the uniqueness of God from the supposed impossibility of distinguishing infinite things, which would have all the same attributes - he points out that this distinction could still happen through relations or spatio-temporal characteristics. Neither does he approve the attempt to prove the uniqueness from the necessity of God, since there is nothing to show that there are only necessary things. Instead, Crusius favours a rather idiosyncratic proof: gods exist in space, and if there are several gods, they must exist in the same or different space, but in the latter case they would be finite, while the former is impossible.

In addition to these rather general attributes, Crusius’ non-active attributes for God contain also attributes related to what he calls the abstractions of existence or space and time. Here the case of time is perhaps easier to understand, since it just means that God is eternal or exists at all times (he does make the interesting suggestion that Trinity explains what God did before creation of the world: the three persons interacted with one another somehow).

The case of space is quite analogous, although Crusius’ result seems unusual: God is immense or they cannot be limited by anything. Crusius notes that this does not mean that God would consist of parts - the usual objection against God’s spatiality. Crusius explains himself by saying that the space of God is a mere abstraction and mere abstractions cannot be really broken into parts.

The active attributes of God refer, then, to those attributes of God that involve an action or a capacity for an action. On a general level, these attributes include that of God having an infinite force, that is, a force that can do everything that just happens to be possible. Some of the actions resulting from God using this force are a necessary part of their essence. Yet, all of them cannot be necessary, Crusius insists, and must be such that God can begin and stop doing them, because otherwise God would be less perfect than humans, who can do this.

Crusius also divides God’s actions into immanent actions that belong merely to the inner state of God’s essence and transient actions that either create a new substance or change the condition of a substance different from God. But can God create something different from itself, if God exists everywhere? Yes, Crusius asserts, as although two gods cannot occupy space, apparently God and a finite creature can.

Crusius notes that there are three kinds of actions: movement, understanding and will. Of these, God really cannot move, because as has been noted, God is everywhere. Then again, Crusius notes, God can definitely understand or think things - denying this would be implicit atheism, because otherwise God would be just a blind mechanism.

God’s understanding, Crusius says, should be infinite. This means, firstly, that God knows all there is and all there could be. Secondly, it means that God’s knowledge of actualities and possibilities must be perfect. For instance, God cannot take impossibilities as possibilities, God must know everything as distinctly as possible and therefore God definitely cannot know anything through sensations or deductions.

Crusius points out that God knows different things in a different manner. Some things, like possibilities and God’s own existence, God would know even if the world did not exist. God also has an encompassing vision of the world: its past, present and future. This vision includes, Crusius insists, also the actions of free creatures - we cannot understand how God can know them, but it is not contradictory. Between the two types of knowledge, Crusius states, God has also a third type: knowledge of what would happen, if a free person chose to do something.

In addition to understanding, Crusius assures us, God also has a will. Just like with divine actions, some of God’s volitions are necessary - these are God’s fundamental desires. With humans, Crusius recounts, fundamental desires include drive toward perfection, drive to share perfection to others, drive of conscience and bodily drive. The two latter cannot really be divine drives, but the two others can. God thus always desires to be perfect, and because they are, God is always infinitely happy or blessed.

God also desires perfection in things created, Crusius says, and this means that the world, if such exists, must form a moral system, where choices of free creatures can reflect divine perfection and all the other things can serve free creatures in fulfilling this purpose. Acting in accordance with divine perfection, Crusius suggests, means especially that free creatures must understand their dependence on God. God must thus give the free creatures laws that must be obeyed, and if the laws are not obeyed, God must punish the sinner. Crusius goes even further and insists that God can never really end the punishment, because this would mean that transgression would ultimately be forgotten and justice would not be served. He does concede that this might not mean that God would put sinners in an eternal torture, but only that a sinner is prevented from reaching the highest state of happiness possible.

Why did God then allow sinners to exist in the first place? Crusius’ first line of defence is that sinners were not created as sinners, but they freely chose to be such. Yet, this line of defence seems inadequate, since God still knew that the sinners would sin. Crusius’ second and rather cruel defence is that God had to be shown as a stern and righteous judge, since righteous punishment of sinners is a perfection.

In addition to punishing the sinners, God’s righteousness demands also rewarding the virtuous. Yet, God has also further reasons for this, since the second fundamental drive of God, Crusius says, is a desire to do good and show love to free creatures. Thus, God’s dice are loaded toward mercy and charity. Still, Crusius says, God won’t just hand out maximal amount of goodness to every creature, since this is ultimately impossible: there is no maximal goodness for finite creatures, since their goodness can always be increased.

In addition to these fundamental desires, God also has freedom, Crusius insists, that is, God can begin actions that otherwise wouldn’t have happened. This does not mean that even God’s free actions would be completely against their fundamental desires, in other words, that they wouldn’t satisfy God's desire for perfection and goodness. It is more that God has a complete freedom of not creating such a world at all, but has freely chosen to create it. Furthermore, Crusius emphasises, world could also have been otherwise, since God could have chosen many different means to fulfill the perfection of the world.

Christian August Crusius: Draft of necessary truths of reason, in so far as they are set opposite to contingent ones - Proving God’s existence

Diverging clearly from the Wolffian order of metaphysics, Crusius proceeds after ontology to natural theology. His justification is that while knowing the properties of things in the world requires knowing the properties of their creator, natural theology presupposes only a general concept of the world as a sum of all things, of which we we perceive a part and of which we ourselves are a part, and additionally some individual truths about souls.

Crusius’ first task in natural theology is to prove the existence of God, that is, an intelligent and necessary substance, which differs from the world and is the effective cause of the world. Crusius’ strategy is to throw everything at the wall and see what happens to stick, as he is willing to provide a whole bunch of different proofs, deeming the topic so important that it must be decided by any means necessary - the various proofs convince different people and corroborate one another. Crusius doesn’t even provide any other systematisation of this hodgepodge of proofs, except a classification based on the supposed strength of them.

The most certain proofs, Crusius says, are demonstrations that are ultimately based on the three principles of human cognition and of course principles derivable from them, such as the principle of sufficient reason and the principle of contingency (things that can be thought not to exist are contingent). Crusius presents altogether five of these demonstrations, all of which can be regarded as modifications of the cosmological proof in the Kantian classification. I will not go in detail to these proofs, but merely note their prominent features:

• Crusius bases the existence of complex things on the existence of simple things, which they consist of. Then he uses the principle of contingency to show that simple things in the world are contingent and so require God for their existence.
• Crusius argues, as we have seen, that there are no infinite series of changes. This means, he insists, that the world must have been created by a substance that has existed eternally before creation.
• Crusius notes that all series of movements must be ultimately derived from an action of an infinite force.
• Crusius also uses the principle of contingency to directly conclude that the world is contingent.
• Crusius insists that plant and animal species must have originated from single individuals, which due to their well ordered nature must have been created by God.

The last of the demonstrations provides also a sort of link to what Crusius calls an infinitely probable proof of God’s existence. This proof is basically the old argument from the order in the world to someone creating it in an orderly fashion. Crusius insists that it is not just a question of teleology - it is a question of plants, animals and other things having a well ordered structure and not just them being mere means for human purposes.

Crusius admits that it is possible that this order would have been fashioned from blind chaos by pure chance, or as Crusius suggests some atheists said, by a revolution in the structure of the world. Yet, Crusius instantly counters, such a revolution would have required an infinite number of coincidences, making the only option or the existence of God thus infinitely probable. Indeed, he argues, this proof shows clearest why God would have to be an intelligent substance and not mere force of nature.

The final or the lowest level of the proofs in Crusius scheme consists of such that result in finite probability. First two of those involve history. Crusius argues that the oldest history books (by which Crusius refers especially to the Bible and other myths) assume that the humankind has not existed forever and it is not probable that the first humans would have been created with natural means that do not work nowadays (e.g. humans being generated in the bowels of the earth). Furthermore, Crusius emphasises that during human history all nations have believed in some divine being or beings and asserts the improbability of a so widely spread deception.

Third of the merely probable proofs is based on the supposition that all humans have a conscience or a natural propensity to know what is right and what is wrong. Crusius argues that the universal existence of such a propensity cannot be a mere coincidence, generated by lucky circumstances, but must have been planned by the creator of humankind to help humans to decide what to do and what to avoid doing.

There is a conspicuous absence in Crusius’ battery of proofs - the ontological, or as it was then often called, the Cartesian proof. I noticed in an earlier post that Crusius would have accepted the proof in his ontology, but his theology clarifies that this is not the case - no proof of God’s existence can be based on a mere principle of contradiction, but some consideration of causality must happen. Crusius’ justification is evidently inherited from Hoffmann: although we cannot think the most perfect being without accepting its existence in our thoughts, this does not tell whether the most perfect being has existence outside our thoughts. If it would be a valid, Crusius adds, we might as well prove that the most perfect man and woman must exist, although the existence of men and women altogether is contingent.

What the Cartesian proof does say, according to Crusius, is that if God’s existence has been guaranteed otherwise, we can say this existence is necessary. This strategy is not that far from Wolff’s, who first proved God’s existence through a cosmological argument and then proceeded to show through an ontological argument why God must exist (because God is the most perfect being).

The main target of Crusius’ proofs are atheists. Crusius includes under atheists also people who doubt God’s existence. Such doubting atheists attack only the supposed weaknesses in the proofs of God’s existence, for instance, they might reject proof from the order in the world by pointing out imperfections in the world. Crusius’ answer to this particular objection is that what is imperfection from a limited point of view can actually contribute to the perfection of the whole world.

Another point the doubting atheists make, Crusius says, is that humans cannot really have a perfect conception of God and therefore it is as reasonable to deny as to accept God’s existence. Crusius insists that we do not need such a fully adequate concept of God to speak about their existence, but we have to just be able to distinguish God from other things. God is no empty word, Crusius assures, although we as finite things can know God mostly through negations or through God’s relations to other entities.

The more strict atheists, Crusius says, deny outright the existence of God. Some of these atheists are materialists, like ancient atomists, who consider even thinking and willing to be mere movement of matter and who do deny the existence of all simple intelligent substances. Other atheists Crusius groups under the title of universalists. Universalists he divides into those like Anaximander, who suppose that the final cause of the world can lie in the simple substances of the world, which may be intelligent, and those like Spinoza, who think of world as a unified simple substance, with things in it as mere properties of the substance. All of these forms of atheism, Crusius thinks, fall short in that they have to assume an infinite series of causes.

Crusius ends the discussion of the existence of God by noting that atheism is not the only erroneous view on theological matters. There are also deists, or as he also calls them, virtual atheists, who do not deny the existence of God, but only that of God being a moral lawgiver and judge. This is a topic he leaves for the next chapter on the attributes of God.

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 - Measuring quantities

A common topic in ontologies of Crusius’ time, not that usual in modern ontologies, is quantities - back then, general philosophers were keen to explain what mathematics is all about, while nowadays this question is more and more left for special branch called philosophy of mathematics. Crusius follows the tradition and starts by defining quantity as such a property of a thing, by which something is posited more than once.

Crusius notes that at least complex concrete things naturally have a quantity - they consist of many things. Furthermore, even simple concrete things have quantifiable features - they have forces, and even though they are indivisible, they still are spatial and thus have some magnitude. Then again, some abstractions are not quantifiable, Crusius says: there are no levels of existence, but all existing things exist as much as others. Crusius also notes in passing the possibility of infinite quantities, but at once declares that we finite beings cannot really know anything about them.

Quantities come in different types, Crusius continues, for instance, quantity of a force differs from a quantity of an extension. The difference between these types becomes important, when we start to measure the quantities. Measuring, Crusius says, involves determining a relation of a quantity to some known quantity. As such, this kind of comparison is possible only between quantities of the same type (there’s no sense in measuring weight with a ruler). Still, Crusius admits, quantities of different type can be compared indirectly. Firstly, we can compare them through relations of quantities - for instance, we can say that punishments should be proportional to the crimes punished. Secondly, the comparison can be done through causal links, for example, the resistance of a body can be compared with the striving of a soul, because one has the effect of hindering the other.

To determine a quantity perfectly, Crusius says, we must represent its parts distinctly. This requires expressing the quantity as a number of distinctly thought units. These units might be naturally distinct - for instance, when we count things distinguished by natural limits, like cows - or arbitrarily chosen, for example, when we compare length of a thing to a measuring stick. Since a given quantity might not be expressible as a number of arbitrarily chosen units, Crusius also introduces fractions (no mention of irrational numbers, though).

An extreme case of natural units, for Crusius, is naturally provided by simple substances. Crusius admits that measuring complex substances by their simple parts is impossible, since we do not perceive these ultimate constituents. Still, he continues, understanding the nature of these simple parts can help us in picking suitable units for measurement: for instance, when we note that movement should be ideally measured by checking how many simple substances move through smallest measures of space, we can surmise that movement could be measured by checking how many things move through a certain space.

Crusius spends the majority of the rest of the chapter discussing a hotly debated topic of the time, namely, the so-called question of living forces. The point of the debate, at least as conceived by Crusius, is how to measure the quantity of an action, such as movement. Crusius’ take is that while abstractly taken this quantity can be expressed as a multiple of the strength of the action (in case of movement, mass of the moving object) and its velocity, we must also account for the resistance encountered by the action and thus use the square of velocity to determine the action.

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 - Necessity and contingency

It has taken Crusius this long to finally get to the definitions of two concepts mentioned in the very title of his book: necessity and contingency. Like definitions of modalities tend to do, Crusius’ are ultimately circular: necessary is what cannot be otherwise, while contingent is what could be otherwise. Yet, he at once gives a more substantial explanation of the terms, linked to causal terms: necessary is such that no cause could make it otherwise, while contingent is such that requires a cause making it so, without which it would be otherwise or not at all.

Crusius also suggests a criterion for recognising what is necessary and contingent: if we cannot think contradictory of something, it must be necessary, while if we can, it must be contingent. Crusius underlines that this criterion is not foolproof and definitely does not reveal the essence of necessity and contingency. Indeed, he points out, even a fatalist could think that a world might be otherwise, even if his worldview would mean that the world is necessarily what it is.

Crusius notes that necessity and contingency can concern both the essence and the existence of a thing. In case of essence, he clarifies, the question is whether a thing cannot have different properties, because changing them would make the existence of the thing impossible - this means that the essence is necessary.

Necessity and contingency of the existence of a thing, then, refer to the respective impossibility and possibility of the non-being of the thing. Crusius notes that necessary existence of a thing can be either independent necessity, where the thing exists continuously and is necessary in all circumstances, or consecutive necessity, where the thing exists necessarily in certain circumstances, when it is generated. Respectively, contingent existence of a thing can be either dependent contingency, where thing doesn’t always exist, but must have an origin, and consecutive contingency, where thing is generated in such a manner that it might have been otherwise or even not at all.

Crusius’s concepts of independent and consecutive necessity resemble the concepts of absolute and hypothetical necessity in Wolffian tradition. Yet, Crusius sees a difference. He defines absolute necessity as something, which as such cannot be otherwise. The most obvious type of absolute necessity, Crusius notes, is such where contradictory opposite of something contradicts the very principle of non-contradiction - something which many Wolffians also recognised - but it is not the only type, since similar forms of necessity should arise also from the other two basic principles.

The hypothetical necessity Crusius defines as such where something cannot be otherwise in certain circumstances that are based on a series of conditions, ultimately caused by something that at the moment of its occurrence could have happened otherwise. This concept of hypothetical necessity is obviously a form of consecutive necessity, but with a distinct characteristic that it is based on some free action. On the other hand, if no such free action is to be found behind consecutive necessity, then it will be, Crusius insists, just absolute necessity. This distinction is especially geared against the notion that God would have had to create the best possible world, without any free choice in the matter, which would make the existence of this world absolutely necessary.

Crusius thinks that only such things exist with absolute necessity, where their non-existence would contradict their essence - it is not yet made explicit, but he is clearly implying that only God fits this requirement. All other things are contingent or they could be thought to not exist, so they must have been generated by something else, that is, God. With something of a sleight of a hand, Crusius notes that since these other things cannot then be necessary in the absolute sense of the world - they could fail to exist - but they still have consecutive necessity, being necessitated by the creative act of God, this act of creation must have been free.

Crusius still has some loose ends to tie. Firstly, he notes that complex substances are always generated from their constituents, so that all absolutely necessary substances must be perfectly simple. Secondly, he defines moral versions of all the modal notions he has introduced: this is clearly something that influenced Kant in defining ethical categories of modality. Thus, Crusius begins from the notion of moral existence - what is a goal of a free person, or in effect, what should be - goes on to define moral impossibility - that something shouldn’t be - moral possibility - of which cannot be said that it should or that it shouldn’t be - and finally moral necessity - that something should be done, because of a presupposed goal. These notions and their somewhat strange definitions, where moral impossibility is not contrasted with moral necessity, but with moral existence, parallels closely Kant’s later division of the ethical categories of modality.

Crusius finally discusses the notion of coercion (Zwang), where the necessity of some action is caused by something outside the thing acting. He is especially interested to show that lack of coercion by an external thing still does not mean something would not be necessary - even an uncoerced necessity would be real necessity.

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 - Forces and activities

All things make other things possible and are therefore causes, Crusius says. This possibility of another thing could be called a force. Problem with this definition, Crusius says, is that such forces seem to explain nothing: it does not really tell us anything to say that the stomach has a force to consume food. Indeed, such a force might be a combination of many causes or then it might be just an abstraction of some more substantial process.

For this reason, Crusius advocates looking for forces in a more substantial sense or fundamental forces (Grundkraft). These fundamental forces should be something special and distinct even outside our consideration and also something constant in the thing. When then can we say that something is a fundamental force? Well, Crusius notes, as long as we cannot causally explain the supposed effects through the force, this cannot be fundamental - or at least we do not understand the fundamental force distinctly. This means that at least the first or nearest effects of the fundamental force should be affected only by conditions within the subject. In fact, these nearest effects should be something in the subject itself, while further effects appearing in other things or objects are influenced also by fundamental forces in those objects.

Crusius continues determining fundamental forces. If a fundamental force is finite, it should have only one kind of nearest effect, while all further effects should be understood through these nearest effects - otherwise, causal chains would offer no explanation. Of course, the same finite subject can have several distinct fundamental forces and could thus be part of many kinds of causal chains with many types of nearest effects. Furthermore, the limitation affects even less an infinite force, Crusius says, because it should be capable of literally all kinds of effects. This implies that we can never really know what having an infinite force would feel like.

Fundamental force should be truly fundamental, Crusius emphasises. In other words, it should not be causally dependent on some other forces in the same subject nor be just a modification of some force. Then again, if one knows that some occurrence in a subject cannot be explained through one force, then this occurrence cannot be just a modification of this one force, but requires the influence of some other force. For instance, Crusius suggests against Wolff, human volition cannot be explained through mere force of representation.

Forces can cause something through their mere existence, Crusius says and gives as examples all mechanical causes that affect things through their mere position and shape. Then again, force can also be active in the sense that it affects things through an inner property directed to bring about certain effects. Such activities can form causal chains within a subject, Crusius notes, but these chains must end in some fundamental activities, which are immediate applications of some fundamental forces. These fundamental activities cannot be mechanical, thus, cannot depend on mere movement of the subjects. Furthermore, they cannot depend on anything external to the subject nor be generated merely by a previous activity of the subject, although previous activities can be conditions of a fundamental activity.

Crusius notes that some fundamental activities continue constantly, because of the essence of the underlying substance. In the case of divine activities, Crusius insists, the very underlying substance is necessary and thus the activities are also necessary. If the underlying substance is not necessary, like in case of elements, the fundamental activity is dependent on its existence.

Some fundamental activities do not occur constantly, Crusius says. Of these contingent fundamental activities, some happen always in a certain manner under certain conditions, like human sensations. Then again, other fundamental activities are just enabled by certain conditions, but not necessarily actualised: the primary example here is human will. Crusius insists that such free activities are not contradictory, and indeed, that their existence must be assumed, in order to justify the notion of moral accountability.

Free activities can be sufficient grounds, Crusius says, in the sense that they can make things actual. Then again, he continues, they are not determining grounds, that is, what they make actual could also be otherwise. In cases not involving free activities, Crusius endorses what he calls the principle of determining ground: what is not generated through free action must have a ground that not just makes it actual, but also determines it to be such and not otherwise.

The principle of determining ground concerns only real grounds, in other words, relations between real substances. Thus, Crusius explains, it should not be confused with an epistemic principle that nothing should be assumed without a good ground or reason or with a moral principle that nothing should be done without a good reason. Still, determining grounds do provide us also with ideal or epistemic grounds, he admits: if we know that something is a determining ground for some phenomenon, we know that this phenomenon cannot be otherwise.

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 - What’s in an essence?

An important division of things in Crusius’ ontology we didn’t consider last time is that of incomplete things. An incomplete thing, Crusius explains, is such that, if it should exist, it must be connected to some other thing. A good example would be a location of a thing in relation to other things: clearly, if a location exists, there must be a thing which is located in this manner.

In addition to such external circumstances (umstände) like location, examples of incomplete things, Crusius says, are provided by the relation of subsistence. Crusius has inherited this notion from tradition, but as it is simple and cannot therefore be really defined, it is difficult to understand what is meant by something subsisting in something else. Crusius does provide illustrations of the relation, examples being relation of a certain shape to a piece of matter, understanding to a soul and even foot to a human being. Here, that which subsists Crusius calls property (rather confusingly, because properties were also parts of essence) or predicamental accident, while that where something subsists is called a subject.

In a rather inconsistent manner, Crusius sometimes speaks as if subjects were the stable element in the relation, although in many other places he underlines that subject and its accidents are incomplete and only their combination - essence or substance - is the true complete thing, just like matter and shape or form are just two aspects of a shaped material object, like a book.

Subsistence relation forms chains, with subjects subsisting in further subjects, Crusius explains, just like science subsists in understanding and understanding in soul. Crusius suggests that these chains cannot go on indefinitely, but there must be some absolute subjects, which do not subsist in anything else. Well, to make the matters more difficult, Crusius suggests then that even absolute subjects can subsist in a further subject, just not like a property subsists in a subject.

In some cases a subject is necessarily connected to a certain property, in other cases not, Crusius says. Examples of the latter would be, on the one hand, red colour of a house, on the other hand, person’s ability to speak Latin. These two examples are very different in nature. Someone might not have an ability to speak Latin, without having an ability to speak anything else, Crusius notes. Then again, if the house is not red, it still has some colour. Colour is what Crusius calls a house’s possible way of existence or its determination.

A thing with some determinations missing cannot really exist, Crusius explains, although we can think of such an indeterminate thing as a subject of further determinations. Just like Wolffians, Crusius defines an individual thing as being fully determinate. With all its determinations, an individual is differentiated from all other individuals, while abstractions from individuals can exist only in several individuals.

Crusius also divides properties into positive and negative properties. This division is linked with the notion of determinations in the sense that when we think of a negative property, we then implicitly think of some positive property, but only indeterminately (what is not yellow is still coloured somehow). Crusius divides negative properties further into merely negative and privative determinations (think how it is different to say that coal is not alive and that JFK is not alive). Similarly, he divides positive properties into absolute properties and relations.

To further explain what makes property positive, Crusius states that all of them are forces, that is, they make other things possible or even actual by themselves or with the help of something else. This leads Crusius to deal with the notion of causality. Epistemically, he says, causality is justified by it being impossible to think of something being generated without being an effect of some cause. The corresponding principle of sufficient reason, Crusius insists, cannot be deduced from the principle of non-contradiction, because there is no contradiction when things are different at different times. Furthermore, he continues, causality is a concept we cannot really define - it is so simple that we can only show how this concept can be abstracted from our experience by noting e.g. how our experiences of fire and warmth are linked to one another, without one being part or determination of the other.

Crusius also links causality to what he calls a principle of contingency: what can be thought as not existing must have really not existed at some point in time. The idea behind this principle is that if we then find such a contingent thing existing at some point, it must have been actualised by some force.

Forces or causes are for Crusius one type of ground. There are also other types of ground, he continues. For instance, because a triangle has sides of certain lengths, it must also have angles of certain sizes. Here, the lengths of the sides are a ground for the sizes of the angles, although the sizes clearly do not cause the angles to be of a certain size. Crusius calls such an existential ground.

Both causal ground and existential ground fall under what Crusius calls a real ground: the idea is that in these cases what is grounded is something outside thought. Ideal ground, on the other hand, Crusius defines as something generating knowledge and conviction of something. He also divides ideal grounds into a posteriori and a priori grounds. In an a posteriori ground the concept of what we are about to prove is already present, while the ground at most reveals that this something exists. A priori ground, on the other hand, generates also an idea of what we are grounding.

Returning back from this detour to an essence and its properties, we find Crusius dealing with what he calls the fundamental essence of a thing and attributes, which are constant properties, grounded in the very fundamental essence of the thing. Some of these attributes are necessary or essential: the existence of these attributes is inevitable, once the fundamental essence behind them is supposed to exist. The other type of attribute Crusius deals with is natural attribute or property, which is present in things of certain type usually, but could be absent in extraordinary cases, although the fundamental essence of the thing would remain the same. He notes also that some attributes are based only on the fundamental essence of the thing, while others are based also on external, but constant causes.

Crucius notes also that some attributes mark a real existence of some condition, while others mark only a capacity for something, activated by external causes, contingent activity of the fundamental essence or both. Such activation of capacities makes then possible the change of contingent properties or modi of a thing. By a modus Crusius refers to properties that make an indeterminate thing more determinate by adding to constant properties something variable, which could be replaced by another modus.

Crusius also considers the distinction between a necessary and a contingent fundamental essence. In a necessary fundamental essence properties constituting the fundamental essence of a thing cannot be separated from one another without supposing some contradiction. In this case, also the attributes flowing from the fundamental essence of the thing must be necessary, and indeed, the only thing that can be up to chance is whether the thing itself exists at all. Contingent fundamental essence, on the other hand, refers to a fundamental essence, where some of the constituent properties can be removed without any contradiction. Crusius notes that all finite substances have in this sense a contingent fundamental essence.

These notions lead Crusius to consider a more general question: what does it mean when we consider whether presupposition of a certain determinate essence contradicts a presence or absence of a certain property? His answer is that all this question can reveal is that presence or absence of a property is necessary for a certain concept. Thus, we cannot add a fourth angle to a triangle, without making it not agree with the concept of a triangle. This does not mean that the properties of the thing would be necessary outside our concepts (e.g. a triangle could be changed into a quadrangle). Such a substantial necessity of properties is present only in the cases, Crusius explains, where removal of this necessary property would make the thing incapable of even existing.

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.

Georg Friedrich Meier: Figure of a true philosopher (1745)

Meier’s philosophical work has so far been refreshingly different from what German philosophers of the period in general have been doing. We’ve already seen Meier tackle with the topic of humour, and now he will attempt to paint the picture of a true philosopher in his Abbildung eines wahren weltweisen.

Meier’s motive for writing his work is to eradicate prejudices laymen have against philosophers. Problem is, Meier says, that there are innumerably more philosophers in name only than there are real philosophers. By painting a general picture of a true philosopher Meier aims at silencing critics who fault philosophy for quirks of individual would-be philosophers.

In addition to this advantage of marketing philosophy for non-philosophers, Meier’s image should also serve philosophers themselves. It should serve as an instruction manual for becoming a philosopher and as a measuring stick, with which to evaluate development of oneself and others, even if no human being could ever completely fill the shoes shown in Meier’s image.

Meier borrows Baumgarten’s definition of philosophy as the highest science, concerning general properties of all things, which can be known without the help of faith. Meier admits that a perfect knowledge of philosophy cannot be reached by mere humans, but only by God, who knows literally everything. Meier’s image of a true philosopher takes into account the necessary limitedness of humans: true philosopher, he says, does not try to know more than is humanly possible. Furthermore, a true philosopher knows that humans have more important duties than learning philosophy, like serving other people.

Although humans cannot know everything and shouldn’t spend their lives solely with philosophy, within these limits the true philosopher tries to emulate the divine omniscience, Meier notes. This means, firstly, that the true philosopher should have extensive knowledge of all philosophical disciplines and other fields of learning. This does not mean that they should know everything in an equal fashion. Instead, Meier says, the true philosopher should choose one discipline that they learn extremely well. Thus, different philosophers could specialise in different topics.

Meier remarks that the true philosopher chooses the easiest route to knowledge. Thus, they do not try to learn all by themselves, but read philosophical books and listen to other philosophers. Still, they will also themselves strive to enrich the field of human knowledge with their own investigations.

Not all truths are of equal value, Meier says, but some are of more value and nobility than others. Some truths of lesser value even a true philosopher must know - some of these form a sort of philosophical ABC - but they should strive to know the more valuable ones. Nobility of a truth has nothing to do with it concerning concrete topics, Meier notes, although common people often discredit abstract truth as worthless. Indeed, he continues, the true philosophers are the best to recognise what sort of truth is noble. Meier himself points out two characteristics of such truths. Firstly, such truths and their consequences touch upon many important things, like religion, state, virtue and the happiness of whole humankind. Secondly, knowing noble truths requires more effort, while common truths are easy to know.

In addition to nobility, Meier adds, the true philosopher has to know fruitful truths, that is truths which have many useful consequences. In other words, the true philosopher is no bookworm, but knows what’s most helpful in different walks of life. Then again, Meier insists that all truths could be deduced from other truths and are in principle equally useful. True, we humans cannot always recognise such connections, but the true philosopher should still be ready that a seemingly useless truth will prove to be important for someone else.

Clarity is also a virtue of a true philosopher, Meier says. This means, firstly, that they try to use logic for clarifying what they know by finding signs required for defining things. Meier notes that this is not to be regarded as pedantry. Indeed, the true philosopher is not a mystic, who delights in inclarities. Still, Meier adds, the true philosopher know also the limits of definition and understands that everything cannot be defined so clearly. Thus, they are no charlatans who would offer mere tautologies, when definitions cannot be given. The true philosopher is especially keen on making their own special discipline as clear as possible, leaving petty things undefined.

Meier follows Baumgarten in accepting that clarity means not just logical acuteness, but also strength of representations. Thus, Meier wants that the true philosopher should not try to perfect just their understanding, but also their imagination, wit and other faculties. In other words, the true philosopher should be an aesthetician, who can tell beautifully and vividly about the things they know.

An evident, but quite crucial side of a true philosopher is, Meier emphasises, that they try to be as correct as is humanly possible. Again, this is not completely possible for a human being, but the true philosopher tries to at least minimise the possibility of an error by choosing wilful ignorance over an unfounded dogmatism. In other words, the true philosopher is no blind sectarian.

Truth for Meier does not mean just that something is correct, but also orderliness. Hence, he wants that the true philosopher should also know things in an ordered fashion. This means that the knowledge of the true philosopher is regulated in accordance with the highest principles of knowledge - principles of non-contradiction and sufficient reason. The knowledge of the true philosopher is so ordered in a hierarchy of disciplines, where some are dependent on more general disciplines.

In addition to having clear knowledge, Meier continues, the true philosopher should have a clear notion of knowing these things. In other words, they should be certain of their knowledge. The way to make one’s knowledge more certain, Meier says, is to demonstrate it, of if that is not possible, to back it up with lesser justifications. Of course, full certainty is not always possible for a human being nor is it a guarantee for the truth of something. Thus, Meier admits, the true philosopher is ready to accept things only hypothetically, until further evidence clears the matter.

Meier is also adamant that the true philosopher should put their knowledge into practice. In principle, Meier says, this could be done with any knowledge. Yet, it is especially true about knowledge concerning ourselves, that is, anthropology, which Meier takes to be of utmost importance to the true philosopher. Furthermore, he continues, the true philosopher should take the duties of practical philosophy seriously and find in them motives for their actions.

Meier also notes the true philosopher should have good motives for learning philosophy. We have already mentioned one of them, namely, that of emulating God and thus perfecting oneself. In addition, he remarks, the true philosopher is motivated to help others, and in general, to work for the good of the whole humanity.

Christian Wolff: Natural right 5 - Serving others

Wolff ends this hodgepodge of a book with the notion of servitus. Wolff’s definition of servitus might at first seem rather difficult to comprehend - servitus is a right one has to a thing of another person. The idea becomes clearer when we move from this abstract level to more concrete examples. One particular instance of servitus is such where a person is allowed to walk or ride through another person’s estate to their own. Other types of servitus might involve a right to hunt in neighbour’s land, right to collect nuts or berries from it or a right to draw water from a well in it.

All the examples just given involve estates in a more rural area, but there are forms of servitus that are appropriate to more urban living areas. Thus, in one type of servitus a building may use the wall of another building as a supporting structure. Furthermore, the examples have all been affirmative in the sense that they allow a person to do something to the thing of another. Another type of servitus is negative in the sense that it involves a right to prevent an owner from doing something. For instance, an owner of an estate might be prevented from building a too tall building that would obstruct the view of the neighbour.

Majority of servitus are, Wolff insists, based on the free choice of the owners of the things in question. Yet, he admits, some of them might be obligated by the natural law. For instance, an owner of a building should take care that neighbouring buildings still receive enough light for normal proceedings of life. Thus, a building owner might be obligated into a servitus, where their neighbour is able to demand the placement of windows on their building, so that light can come through to the neighbouring estate.

All the examples of servitus presented thus far have been what Wolff calls a real servitus, that is, they involve relations between two estates. This type of servitus remains valid, even if the owner of the estate changes. A completely different is the case with what Wolff calls personal servitus, which is tied to a certain person and is cancelled e.g. if the person in question dies. A good example of this type of servitus is usufruct, in which a person is allowed to use a thing belonging to another person and even gather profits from it, as long as the thing in question remains substantially same.