Per sophisma figurae dictionis

Major premise: That which is a subject, is substance

Minor premise: A thinking being can only be thought of as subject

Conclusion: Therefore, every thinking being is substance


Kant describes the fallacy of the syllogism in the context of transcendental philosophy, and therefore making reference to (so to speak) transcendental cognitive structure. This is no accidental, because for him, the transcendental illusion is not merely logical, and therefore he distinguishes it from the fallacy, which is logical. The difference, I think, is established in passages like this:

«For we have here to do with a natural and unavoidable illusion, which rests upon subjective principles and imposes these upon us as objective, while logical dialectic, in the detection of sophisms, has to do merely with an error in the logical consequence of the propositions, or with an artificially constructed illusion, in imitation of the natural error. There is, therefore, a natural and unavoidable dialectic of pure reason--not that in which the bungler, from want of the requisite knowledge, involves himself, nor that which the sophist devises for the purpose of misleading, but that which is an inseparable adjunct of human reason, and which, even after its illusions have been exposed, does not cease to deceive, and continually to lead reason into momentary errors, which it becomes necessary continually to remove.»
(Critique of Pure Reason)

It may be noticed here somehow Cartesian discarded hypothesis on the meditation about the supreme being. The major premise, Kant says, refers to a being that can be given in an intuition as an object, while in the minor it is only considered in relation to the thinking and the unity of consciousness, but not to intuition as it can be given as an object of it. Everything clear up to this point, but in a footnote the obscureness returns. There, what it is said is that in each of both premises, it is the term thinking what is taken in two different senses. That is, again: in the major, as directed at an object of a possible intuition, in the minor in reference to self-consciousness, without reference to any object.

But where does the conviction of Kant on his own hypothesis of inclination for error of reason takes its grounds? It should be noticed that his place is not precisely conditioned by his criticism, but rather the contrary. And on the other hand, considering the proposition in itself: in which way is more profitable, taking the subject in its broadest sense, raising it to the level of pure form of all thought in general, or taking it as a singular term, and related to certain thoughts that are inherent to it in a particular way?

Notice, for example, that the amphibology (which produces the fallacy) does not concern so much to the term thinking but rather to subject, which serves as a medium. The first case, in fact, could not take place according to the syllogism which we have set out here. Kant stated it this way: «That which cannot be cogitated otherwise than as subject, does not exist otherwise than as subject, and is therefore substance». But the ambiguity is in the word subject: first subject as substrate of attributes, then as medium of all thoughts. Maybe because a question of time, i.e. the diachrony inherent to language, today we see the thing more simply, and this leads us to see the seeds of illusory appearance not transcendental, but merely logical. But this does not mean that Kant's intuition on this point has been entirely wrong and that some of its validity is preserved over time, although in other shapes.

Kant says (in the second edition of the Critique in question, which reformulates what concerns the paralogisms of pure reason):

«the proposition 'I think' (in the problematical sense) contains the form of every judgement in general and is the constant accompaniment of all the categories»²

Since it is "taken problematically" this I think might be thought as an idea in itself that could not be known speculatively. This means that it is not, for example, an immediate certainty obtained from an experience (that of consciousness in relation to it self in it's speculation), from which infer it existence through any syllogism. Kant conceived the Ego, on contrary, as:

«nothing but the simple and in itself perfectly contentless representation "I" which cannot even be called a conception, but merely a consciousness which accompanies all conceptions. By this "I," or "He," or "It," who or which thinks, nothing more is represented than a transcendental subject of thought = x, which is cognized only by means of the thoughts that are its predicates, and of which, apart from these, we cannot form the least conception.»³.


This topic of the rational doctrine of the subject or thing that thinks -as a problematic concept- could not then contain any substantiality (immateriality) or simplicity (incorruptibility) or identity (personality).

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(1) Kant, Critique of Pure Reason.
(2) Ibíd.
(3) Ibíd.


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