Christian Wolff: Reasonable thoughts on God, world, and human soul, furthermore, of all things in general - Truth vs. dreams

At least since the days of Descartes the problem of the reality has perplexed philosophers. Is the world that we perceive truly real, and not a mere dream, hallusination, figment created by a powerful daemon or mere fiction fed into our brain by a mad scientist? Wolff himself notes the problem, but apparently fails to take it very seriously. Wolff simply decrees that in dreams all processes are less ordered than the truth. By order Wolff means the occurence of some similarity, that is, of a pattern or a rule, which the things follow. Ultimately the basic criterion is the principle of sufficient reason or causality: processes in dreams do not follow any causal laws.

Wolff's criterion is perhaps enough for distinguishing our usual dreams from what we happen to call reality. He is not interested of a possibility that a new, even more real world might be discovered beyond the world of experience. This might be a consequence of Wolff's pragmatic nature – after all, there has to be some limit for the demand of indubitability. Furthermore, Wolff could continue, if we some day discover that we have been dreaming all along, at least this discovery will be made through the very same criterion of the regularity of processses. Here Wolff is once again paving the way for German idealists, who also had some doubts about the need to find any ultimate reality beyond the world of experience.

In modern analytic philosophy one is accustomed to mean by truth a characteristic of propositions, beliefs etc., while here Wolff essentially refers by truth to the reality. Furthermore, he almost instantly extends the notion of truth to apply to all sorts of processes. Truth thus becomes a quantifiable characteristic: the more regular and law-governed a thing is, the truer it is.

Wolff also introduces the notion of perfection (Vollkommenheit), which he then immediately characterises as a coherence of a manifold, which is yet another form of regularity in addition to truth as a regularity of processes. The regularity in its various guises appears then to be the primary value characterising simple things: the goal the finite simple things try to acheive is the regularity both in their internal processes and in the system of things they causally engage with.

Like with truth, Wolff also suggests that perfection is a quantifiable characteristic. Indeed, he appears to suggest that there could be a calculus of perfections for counting from individual perfections the quantity of their combination. Yet, the value of this combination is not a simple sum of the perfections, because one must also take into account how well the perfections fit together. For instance, the perfection of a house is not to be determined by its beauty and its utility, but one must also consider how well the beauty and the utility serve one another.

A complex thing with several constituent perfections might not then be perfect as a whole, if the perfections clash with one another. Similarly, harmony of apparent imperfections can produce a greater total perfection. It takes no Leibniz-scholar too see where this line of reasoning is heading to – we might indeed live in the best possible world, although its individual elements might seem quite unpleasant.

Before moving to the next issue, I will shortly recapitulate what Wolff has to say about the division of things. We have essentially three possible types of entities. Firstly, there are the complex finite things, and we know from experience that they exist all around us. Indeed, the whole world is a complex of all finite things. Then there are the finite simple things, and we know that at least some of them must exist – otherwise we wouldn't have even complex things to discuss about. Furthermore, although we do not yet know it, our own soul will also probably be finite, but simple. Finally, there might be an infinite thing, although we do not yet know whether there is any actual infinite thing – if there is, it will play the traditional role of God. Thus, even in his ontology Wolff has preliminarily outlined the three other parts of metaphysics: cosmology, psychology and theology. Next time, we shall move to the more concrete parts of Wolffian metaphysics.

Christian Wolff: Reasonable thoughts on God, world, and human soul, furthermore, of all things in general - Units of force

I have always found the concept of infinity, as used by many historical philosophers, to be rather confusing. This is probably due to my own background as a student in mathematics, where by infinity one means a number so great that all the regular numbers are way little in comparison. Because the infinities of which these philosophers speak – particularly God – are supposedly something beyond numbers, I have tried to avoid the ambiguous term. Indeed, one of my articles was once rejected, because the reviewer had something against me speaking of perfections, instead of infinities. Yet, I still feel that the two concepts are rather close. Infinite substance, for instance, is something ”way awesome”, superior in all relevant senses compared to a mere finite substance – shouldn't we then say that it is perfect in comparison with the finite substances?

Wolff describes infinity of a thing as a lack of all bounds (Schranke), and while he never explicitly defines what he means by these bounds, he in several occasions appears to relate them with how a thing is determined and classified. The identification of boundaries and determination resembles Hegel's statement that ”all determination is negation”; Hegel says that he borrowed the statement from Spinoza, and it would be interesting to know how widely it had circulated.

The identification of boundaries/negations and determinations may be difficult to understand. With Wolff, we should remember the notion of essence: a possible structure, which can be actualised in concrete things. Essence determines then at least some characteristics of an actual thing, but other characteristics might be determined by its relations to other things. These relations, then, are what bound the essence and divide it into different species: if the essence in question would be a hole in the wall, the windows and the doors would be differentiated by their differing relations to persons using them. The word ”boundary” is here used somewhat metaphorically: boundaries of a figure are also its relations to the things surrounding it. Essence and all the relations determine then an individual thing completely, because by knowing the essence of a thing and its relations to other things we know everything there is to know about the thing.

Infinite thing is then something that is not bounded, that is, it is determined only by its own essence and not by any relations to other things. In other words, an infinite thing cannot be distinguished from other infinite things. Instead, it is completely inclassifiable – it cannot be put into a same class with finite things, because their nature or essence is too dissimilar. Thus, all we can do to describe an infinite thing is to use meaningless superlatives – it is beyond anything we can imagine, or indeed, just ”way awesome”.

How does the division of infinite and finite things then relate to the earlied division of simple and complex things? Wolff notes that infinite things cannot really change, and by change he means specifically a change of the bounding relations: an essence of a thing cannot be changed, but at most one can replace a thing having one essence with another thing having a different essence. Infinite thing is then all that it is ”at once” and not by going through successive stages. Then again, a complex thing might change e.g. its spatial characteristics, which for Wolff are essentially relations to other things. Thus, an infinite thing, as atemporal, must be simple.

Complex and infinite things are then two classes with no common members, but are there any finite simple things? Well, all the complex things, says Wolff, must be founded on some simple things, the combination of which has generated the complex thing. Now, a combination of simple things is undoubtedly a relation of them, and furthermore, a relation which might change. Thus, the simple things that are the final constituents of complex things must be capable of change and therefore finite.

Boundaries of complex things can be spatial or relate to the number of things it consists of, but what about boundaries of a simple thing, which is not spatial and does not consist of other objects? Remember that by boundary Wolff refers to a non-essential classification caused by the relations of a thing to other things. He apparently seems to think that such a classification must at least be analogical with the relations of magnitudes. A good example of this sort of scale would be one consisting of temperatures: temperatures do not consist of smaller temperatures, although they can be related like one number relates to another. Wolff calls quantities of such scale grades: this concept was used later by Kant and Hegel.

Wolff shares with Kant and Hegel also the idea of relating grades to forces (Kraft). Indeed, beyond numeric and spatial magnitudes, it is rather difficult to imagine any quantities, but those which measure the effects of a thing. For instance, temperature can be quantified, because a certain grade of temperature has a clear effect on the size of certain substances. Thus, Hegel later suggested that all grade-scales are not just similarly structured as scales of numeric and spatial magnitudes, but also essentially connected to such.

Wolff's simple, but finite things are thus indivisible units of forces. In this Wolff appears to move beyond Leibnizian monadology, where the ontological units were characterised by perception, and towards the identification of activity as the most essential characteristic of true existence, which is a common theme in German idealists.

By a force, furthermore, Wolff does not mean a mere capacity, the activation of which is completely contingent. Instead, force is active and causes some effects, unless it is countered by a contrary force. Furthermore, the force of a finite thing is bounded or has a definite grade. In other words, the activity of a simple, finite thing is somehow limited. This limitation is not essential, and the simple, finite thing could well change it, which proves the possibility of applying temporal terms to these things.

Wolff does not stop here, but suggests that simple things are constantly striving towards changing their boundaries. Wolff's only justification for this statement appears to be the principle of contradiction: a thing cannot counteract its own actions. The justification appears once again

somewhat loose: although the thing itself cannot nullify its own force, other things might well affect the thing, that is, if the opposing force is strong enough, the simple thing becomes to a standstill or even starts to become weaker. Wolff also apparently thinks that static states of standstill are merely transitory phenomena, which cannot hinder the almost constant change of the strength of the forces.

We could thus picture a finite simple substance through a graph where every moment of time is connected with some grade in the scale measuring the quantity of the force. The graph goes up, when the force achieves its goals, and when it goes down, it is hindered by other forces. In the shadowy distance above, there is the infinity, unreachable by mere finite things.

Wolff does not say as much, but it appears reasonable to suppose that it is this infinity towards which the finite substances probably strive. The notion of infinity thus produces an objective criteria for making value judgements in the realm of finite substances: the more the finite things resemble the infinite thing, the better they are. We shall see next time what sort of value scale of things Wolff suggests.

Christian Wolff: Reasonable thoughts on God, world, and human soul, furthermore, of all things in general - Relational view of space and time

In the years 1715 and 1716 a philosophically significant correspondence occurred between Leibniz and Samuel Clarke, a proponent of Isaac Newton. Particularly Leibniz attacked the Newtonian idea of an absolute space and an absolute time that exist independently of any things within them. Leibniz based his criticism on the principle of sufficient reason: if there would be an absolute space, God might have created world few meters away from its actual place in the absolute space, but since all the places in an absolute space are completely similar, He would have had no reason to create it in any particular place and would thus have been unable to create the world anywhere.

Instead of an absolute space and time, Leibniz suggested a relational view of them: space and time are nothing but orders of things – space an order of coexistent things and time an order of successive things. An important consequence of this view is that it becomes meaningless to speak of space and time without any things. (Note that this view is not relativistic: spatial and temporal magnitudes are still stable, despite the differences in the velocity or the effects of gravity.)

Leibniz's view was accepted by Wolff, and indeed, it appears to have been in favour throughout the German idealism. Kant, for instance, appears to take Leibniz's view more seriously than Newtonian absolute space: Kant attacks in Critique of pure reason the relational view more vigorously and also appears to apply a modified relational theory of space in his metaphysical foundations of natural science. Indeed, presupposing an absolute space and time adds to an ontological system two rather strange entities, which are not things as such, but also not based on things.

Now, if one would take Leibniz's description of relational view literally, one could instantly derive all sorts of absurdities. For instance, if space was nothing more than an order of things, space would change at once, when the order of things changes: space would become larger, if a thing went farther from all other things than any thing before. As Leibniz himself appears to have been aware, these problems could be avoided by defining space and time through possible, rather than actual order of things. Thus, space could continue beyond the actual positions of things, because the things have the capacity to or at least could be conceived to move further than they are.

Wolff, on the other hand, seems not to be aware of the possible problems and suggests that space and time could be defined as the actual order of things. Thus, he is able to say that even a single thing by itself would be non-spatial or that spatiality required at least two things and their actual relation.

Because Wolff's simple things should have no things as their constituents, their internal constitution could not be spatial, because it would involve no actual relation of several objects. As we noticed in the previous text, Wolffian notion of a simple thing is ambiguous, because it leaves out the possibility of Aristotle's potentially divisible and still actually unified substances. Similar problems arise with Wolff's notion of space. According to Wolff's definition, the Aristotelian divisible substance without any actual parts would be non-spatial, which is clearly absurd, when we think of e.g. a portion of water. Here we should obviously add some modalities to Wolffian account of space: Aristotelian substance is spatial, because it can be divided into parts that have spatial relations.

Even this correction might not be sufficient. Democritean atoms were supposedly indivisible substances, but still spatial. Wolff notes – consistently with his own definition of space – that this atomist notion is contradictory. Yet, it seems quite possible to imagine that a thing would be physically indivisible and still have some spatial magnitude: spatiality is here not connected to a capacity to divide a thing, but to a possibility of conceiving the division of a thing.

For Wolff, spatiality is something connected with the inner consitution of complex things. What sort of characteristics are then left for simple things? I shall return to this question in the next blog text.

Christian Wolff: Reasonable thoughts on God, world, and human soul, furthermore, of all things in general - Lego block view of the world

System builders do love to divide things into two classes (unless they are German idealists and probably more into threefold divisions). Wolff follows this tradition and distinguishes between simple and complex things. (By the way, one just has to appreciate German language for its capacity to make such important concepts easy to grasp. Simple things are ”einfache”, which could be translated as ”one-folded” - simple thing has but one part. Complex things, on the other hand, are ”zusammengesetzt” or ”put together” out of smaller things. English equivalents are less transparent.)

How does Wolff then justify his division? The existence of the complex or assembled objects he accepts as given in our experience: the things outside us can be seen to consist of smaller things. In addition to being assembled of other things, complex things have various other characteristic properties:

• complex things have a magnitude (after all, they consist of many things)
• complex things fill space and are shaped in some manner
• complex things can be enlarged or diminished and the order of their parts can be varied without changing anything essential
• complex things can be generated by putting things together, and they can be destroyed by separating the constituents
• the existence of the complex things is always contingent
• the generation of complex things takes time and is humanly intelligible

Simple things, on the other hand, cannot be found in the experience, Wolff says, so their existence must be deduced. Here Wolff invokes the principle of the sufficient reason: the existence of a complex thing cannot be explained completely, unless there is some final level of things from which the complex thing has been assembled. These simple things have then characteristics completely different from the complex things:

• simple things do not have any magnitude
• simple things do not fill space nor do they have any figure
• simple things cannot change their internal constitution (because they do not have one)
• simple things cannot be assembled from other things nor can they be disassembled; they can only be generated ”at a single blow” (einmahl)
• simple things are either necessary or generated through something necessary
• the generation of simple things is atemporal and non-intelligible to humans

Wolff's scheme reminds one probably of atomism, yet, atoms have usually not been described as non-spatial: in this Wolff's simple things resemble Leibnizian monads. Yet, if we ignore for now the nature of space, which I shall be discussing next time, we can discern a common pattern shared by atomism, Leibnizian monadology and Wolffian ontology of simple and complex things.

This pattern is based on the idea that world is like a game with legos. There are magnificient buildings and vehicles, but they are all made out of small objects – lego blocks – which in themselves cannot be broken down to smaller pieces. No complex of legos is necessary and you can even see the revealing lines that tell how to disassemble a ten-story castle into individual blocks. Indeed, in all the various combinations, lego blocks remain distinct individuals that just happen to be attached together.

The lego block view of the world is so common these days that it is difficult to remember other possibilities. It was different with Aristotle, who in his physical studies casually notes that substances might also be mixed, that is, combined in such a manner that the combined substance vanish and a new substance appears in their place. We may easily picture such a mix through an example of adding sugar to water: the powdery sugar vanishes, but also mere water, and in place of the two a sugary liquid appears.

One might oppose my example with the observation that the sugar and the water do not really vanish when mixed, but sugar molecules merely disperse among the water molecules. Yet, this observation itself is based on empirical studies and one could not decide a priori whether this particular case was a true mix or a mere assembling of lego blocks. In other words, the example shows that Aristotelian mixes are a conceivable possibility. Furthermore, it is also a possibility which we could well comprehend and imagine: we could model any Aristotelian mix through the picture of sugar combining with water.

Indeed, we need even not think of mixing two substances of different sorts. It suffices to picture a portion of water combining with another portion of water. The result is not two portions of water, but one bigger portion, or in other words, the original things have vanished in combination and been replaced by a new thing. This conceptual possibility is ingrained in the mass terms of some languages: things like water do not appear to behave like the lego block model, thus, we cannot e.g. speak meaningfully of several waters (we have to speak of many portions of water etc.)

If the possibility of an Aristotelian mix is admitted, Wolff's whole division of simple and complex things becomes somewhat suspect. The simple things should, on the one hand, be the ultimate constituents, which are required for explaining the existence of the complex objects: they should be the independent substances, while the complex substances are contingently assembled from them.

Then again, simple things should, on the other hand, be indivisible and they could not have been generated through a combination of other things. Yet, if a thing has been or at least could have been generated through an Aristotelian mix, it would not be simple in the second sense, while it well might be simple in the first sense, that is, an independent substance. In other words, a substance might be generated from other substances, but still not have any parts or constituents.

Wolff himself actually considers the possibility that a simple thing could just change into other simple things, somewhat like Aristotelian elements – fire, air, water and earth – can change into one another. Yet, he quickly disregards this possibility, because either it would be a miracle where one substance is instantly destroyed and another takes it place or then the apparently independent things are mere states of one thing. Only with the latter option, Wolff adds, does the previous state explain the latter state.

Wolff's denial of Aristotelian change of elements is itself unfounded. Even less convincing it is as a criticism of an Aristotelian mix. Although an apparent change of one thing to another thing should be interpreted as a mere change of state, an Aristotelian mix involves a combination of several things into one unified thing, and it feels rather awkward to call two separate things a mere state of their combination or vice versa.

The flaw in Wolff's division of things is important, because it suggests a similar flaw in Kant's second antinomy. The antinomy should consist of two equally convincing statements that could not hold at the same time: ”everything in the world consists of simple things” and ”there is nothing simple in the world”. The two statements could well be both true, if the simple things in the first statement meant final constituents of assembled things, but the simple things in the second statement meant indivisible substances. That is, the final constituents might have no parts, but they could be so manipulated that in place of a particular thing, many things would appear (this division is essentially a reverse of the Aristotelian mix, and indeed, Aristotle himself apparently thought divisions worked this way). We shall have to return to the issue when we get to Kant's Critiques (it will probably take twelve years).

Wolff's theory of simple and complex things has other problems as well. For instance, Wolff merely assumes that simple things cannot be observed. He does not mean that we could not imagine what simple substances would be like, and indeed, he admits that we perceive very small things as having no discernible parts. Yet, Wolff notes that magnifying glasses have proven that these apparently simple things are actually complex – but this empirical evidence does still not prove the general inobservability of simple things.

A more substantial reason for the unobservability of simple things is Wolff's conviction that simple things cannot be spatial, while all observable things are. But why simple things couldn't be spatial? This is a question I will consider next time, when I investigate Wolff's theories of space and time.

Christian Wolff: Reasonable thoughts on God, world, and human soul, furthermore, of all things in general - Bubbles of possibility

Leibnizian philosophy was supposedly based on two principles: the principle of contradiction which states that contradictions cannot exist and which should be the foundation of all logical truths and the principle of sufficient reason which should be the principle of all non-logical truths and which states that all non-logical facts must have an explanation.

Wolff continues the Leibnizian tradition by placing these two principles at the beginning of his ontology. Yet, while the two principles were apparently indemonstrable for Leibniz, Wolff thought that he could deduce the principle of sufficient reason. As the only other axiom from which the principle of sufficient reason could be deduced is the principle of contradiction, Wolff has often been accused of making ontology a mere corollary of logic. I think it will be insightful to see whether this accusation holds.

Although Leibniz's principle speaks of reasons, Wolff's zureichende Grund could as well or even better be translated as a sufficient ground. Ground, then, is something in a thing A that explains why a thing B exists. A and B could be the same thing, but if they happen to be different, A can then be called the cause of B. Warmth of air could thus be a ground for wilting of the plants, while the warm air would be the cause of the same wilting. The principle of sufficient reason in its Wolffian version states thus that all things must have a sufficient ground, that is, something explaining completely how they could exist.

Wolff has two proofs for the principle of sufficent reason. Well, actually there is a third argument – Wolff states that the principle must be assumed if one is to separate a dream from a coherent experience – but this argument is clearly based on the presupposition that we can differentiate the two.

Wolff's main argument is rather simple. Suppose there is something without any ground explaining it. Then it must have been generated out of nothing (Nichts). But as nothing can come out of nothing, everything must have a sufficient ground.

At first sightWolff just appears to beg the question: the statement that something cannot arise out of nothing says just that all things must arise from some previous ground. Yet, we must be careful about how to interpret Wolff's terminology. Nothing, which Wolff speaks of, does not mean a mere state of there being no things. Indeed, Wolff admits that something can come out of a state of there being nothing, as long as it is a possibility that something could come out of this state. Instead, Wolff's nothing refers to something that cannot be or an impossibility: nothing can come out of nothing, because this ”nothing” is an impossibility that cannot ever be actualised.

We are now in the midst of Wolff's use of modal terminology. I should firstly clarify a possible misunderstanding. Nowadays, we are accustomed to speak of possibility and impossibility in connection with propositions: it is possible, for instance, that tomorrow it will rain. For Wolff, on the contrary, possibility is a characteristic of things. Indeed, thing (Ding) means, according to Wolff, something possible. Thus, there are no impossible things (like round squares), or at the most, they are only imagined to be things, although in fact they are mere ”nothings”.

Wolff also tells us that possbility is not by itself an actuality, but requires something to fill itself. This filling of the possibility appears then to be nothing else but the sufficient ground required for the existence of something. We may then picture the Wolffian structure of modalities through the following simile. The possible things are like bubbles in a soup of possibility, all trying to float upwards, to the free air of actuality: they are like forces striving towards actualisation. The possibilities have various chances for reaching the surface, but at least they do have the potential to get there, if a sufficient boost is given. Only the impossible residue at the bottom can never rise towards the actuality, because it lacks the necessary impetus even to strive towards actuality.

We may now return to Wolff's second argument. Wolff asks us to assume two essentially similar things A and B, that is, things that differ only by quantity and location. If the principle of sufficient ground would not hold, A could be changed in some manner that would not occur, if A was replaced with B. But this would contradict the assumption, because similarity is defined by the characteristic that two things could change their place without any essential difference.

Wolff's proof is essentially based on his notion that all things have an essence, that is, a kernel which determines all the other non-quantitative characteristics that the thing has. It is only the essence and characteristics based on it, through which the things can be differentiated. In other words, two completely similar objects must have the same essence.

Wolff's proof suggests that the essence of a thing determines then all the possible changes that can occur to this thing. If a thing would change in a manner not based on the essence of the thing, such a change would violate the essential identity of the thing.: this is the crux of Wolff's second proof. Particularly the essence determines the conditions in which a thing with such an essence can be actualised. In other words, essences are the object of the real definitions of Wolffian methodology.

The bubbles of possibilities in the picture above are then just the Wolffian essences. Note that at least at this point of his discourse Wolff appears to accept the possibility that one essence might have several actualisations distinguished only by their location or their quantity (as I have not yet completed the book, the situation might still change). Here Wolff seems to differ radically from Leibniz, who insisted that two different entities must be differentiated by some intrinsic properties.

Wolff also notes that essences are eternal and necessary. This does not mean that the essences themselves would necessarily have actualisation. He is merely pointing out that if we take possibilities of things as new things – essences – these things must exist. In effect, Wolff is stating that the realm of possibilities is fixed: no new essence could arise nor could any essence be destroyed, that is, neither any impossibility could become possible nor any possibility could become impossibility.

Wolff's framework of modalities undoubtedly can justify the principle of sufficient reason. Indeed, one might say that the principle is built into that framework. But a more doubtful question is how Wolff can justify this system of modalities. Even more confusing is that Wolff connects possibility with non-contradiction. The system of modalities expounded earlier is heavily ontological: possibility of a thing involves some conditions by which it can be actualised. A definition based on non-contradiction would appear to deontologicise the modalities.

The most probable explanation is that Wolff considered contradiction also to be an ontological proposition. Thus, in the previous picture of modality, we should think of all the essences as necessarily related to a counterpart – or all the essences that are not necessary or cannot by themselves be actualised. But the other essences form then pairs, only only one of which can be actualised at the time: the actualisation of one essence keeps its opposite unactualised. The possibilities are then not just forces, but forces combating and cancelling one another.

Even this explanation merely moves the problem a step forward. If Wolff has an ontological notion of contradiction, then the principle of contradiction becomes suddenly quite problematic. Especially the negative possibilities seem quite problematic: although there might be a force striving to generate horses, it seems ridiciluous to suggest that there is an opposite force acting to destroy horses.

As I mentioned previously, Wolff attempts to use the Cartesian starting point as a justification of the principle of contradiction. Wolff's idea is to show that even the Cartesian cogito is based on principle of contradiction: the principle is discovered through one occasion of its use, although once discovered it is self-evident. But it is far from clear that our knowledge of our own existence involves any ontological non-contradiction: I do not believe that I am haunted by a shadow of my non-existence trying to kill me which I would have to actively fight against.

Although Wolff's attempt to prove the principle of sufficient reason is then more complex than meets the eye, in the final reckoning it involves a simple failure. By the way, complex and simple things in general will be the issue next time.

Christian Wolff: Reasonable thoughts on God, world, and human soul, furthermore, of all things in general (1719)

In 1982 appeared a humorous scifi book bearing the lofty title, Life, the universe and everything. Wolff's Vernünfftige Gedancken von Gott, der Welt und der Seele des Menschen, auch allen Dingen überhaupt attempts something similar, just replacing life with soul and adding God as a bonus. But the loftiness is in order, because a new era in German philosophy was about to begin: this is the first ever book on metaphysics in German language.

The words in the title of Wolff's book are not just flowery decoration, but tell quite explicitly what Wolff's book is all about. It investigates, firstly, God. This happens in a discipline that was traditionally called natural theology – that is, based on facts that could be known by a person in a state of nature, while revealed theology relied on Bible and church traditions. Secondly, Wolff's book investigates the physical world or contains a study on cosmology. Thirdly, it investigates human soul, based both on observations of human behaviour (in empirical psychology) and on indubitable reasoning (in rational psychology). Finally, it investigates characteristics shared by all things, that is, ontology. But before any of these discplines can begin, Wolff wants to find an indubitable starting point for his investigation.

In many periods in the philosophy of history, there has been a definitive Philosopher, who one must comment upon, if one is to do serious philosophy – one might not agree in everything with the Philosopher, but even this disagreement must be presented as a commentary on the Philosopher. In the medieval times the Philosopher was Aristotle, in German idealism, Kant, and in certain period of analytical philosophy, Wittgenstein.

In the early 18^th century philosophy the Philosopher appears to be Descartes. We have seen how Lange followed closely in Descartes' footsteps in his description of the natural light of human reason and how Rüdiger took Descartes as one of his main opponents and as the paradigmatic representative of modern physical mechanism. Now we are about to see how Wolff begins philosophy in a Cartesian style.

Indeed, the first paragraphs of Wolff's German metaphysics start from the certainty of the existence of the metaphysical investigator: even if you doubt your own existence, you are at the same time confirming that it is you who is doubting. Even egoists cannot deny this reasoning – egoists being here those who later would be called solipsists, that is, philosophers believing ony in their own existence.

And like Descartes, Wolff uses the discovery of this incontrovertible starting point as an example of the correct methodology. But instead of Descartes' clear and distinct perceptions Wolff inserts his own methodology that we have discussed in earlier texts: our knowledge of our own existence is based on an incontrovertible experience – we are conscious of ourselves and of other things – on an analytical statement – what is conscious, exists – and on rules of syllogistic reasoning.

In fact, it is rather remarkable that according to Wolff, the Cartesian ”I think therefore I am” is a syllogism, when Descartes himself was convinced that it shouldn't be expressed as a syllogism: Cartesian sentence is immediately certain and convincing, while it supposed basis ”all that is conscious exists” is not. The difference reflects the difference in the attitudes of the two philosophers towards syllogistic: Descartes thinking it it an outdated model science and Wolff endorsing it as the true model of science.

Wolff's syllogistic interpretation of Cartesian meditations is interesting also for Kant-scholarship. As we will someday see, Kant expressed the arguments of rational psychology, such as Cartesian cogito, in a syllogistic form. If Kant's criticism would be explicitly targeted only towards Descartes, it would then at least partially miss its point. The existence of the Wolffian interpretation shows that there was a tradition of reading Cartesian sentence as a syllogism and that Kant was probably talking to representative of that tradition.

In addition to methodology, Wolff also uses his Cartesian starting point to ground his ontology, but this will be an issue I shall deal next time. Indeed, I shall probably be spending quite a while with the work: after all, the first German book on metaphysics deserves it.