Доказательство, что предметы могут мыслиться только с помощью категорий, заостряет внимание на функционировании категорий как принципов конституирования объективности в контексте обыденного опытного знания и развивается Кантом в сфере "эмпирической психологии", понимаемой им примерно так, как сейчас нами понимается "феноменология". Наконец, акцентуация того, что категории являются необходимыми функциями единства представлений в самосознании, позволяет Канту положительно ответить на главный вопрос его критической философии о возможности априорных синтетических познаний из чистого рассудка.

S U M M A R Y

To sum up, let us expound the results of our study in a question – answer form.

Why is it important to study deduction of categories? Transcendental deduction of the categories is the core of the Transcendental Analytic, which in turn is the central part of Kant's Critique of Pure Reason. So, in a sense, the deduction is the main part of the theoretical philosophy of Kant. It helps to answer the central question of critical philosophy concerning possibility, scope and borders of synthetic knowledge a priori.

What is the tr. deduction of categories alike? – It is an explanation of the possibility of categories as pure notions of understanding to be the grounds of synthetic knowledge a priori. The explanation is an a priori inquiry itself which does not use any information derived from experience. To be successful, the deduction should make clear that the categories are conditions a priori of the possibility of some kinds of objects. As a result, the tr.deduction confirms the non-sensual origin of the categories.

What is the necessity of deduction for Kant? – If tr. deduction turns to be impossible, the categories could not be recognized as pure notions of understanding and are to be considered as having their origin in experience (main premise of tr. deduction). In this case the sharp distinction between sense and understanding, which is someway a hidden corner-stone of Kant's metaphysics, disappears. The "main premise" of tr. deduction is nothing else as an "argument of Hume" which awoke Kant from his "dogmatic slumber" in 1771.

Is it still possible to build the system of critical philosophy without tr. deduction? – Yes. The possibility of knowledge a priori from pure understanding is already proved when it is known that the tr. deduction of categories is possible, but the fact of its possibility may be ascertained on the basis of metaphysical deduction of categories which proves theirs origin a priori deriving them from the logical functions of judgements, connected with the main premise of tr. deduction (see previous question). This way, however, has some a posteriori "inclusions", because it is already presupposed in the main premise of the tr. deduction that experience conforms, at least approximately, with the rules of understanding; so for Kant, as he wants to reach the highest degree of certainty, the way a priori with the full expounding of the tr. deduction is preferable.

What is the "objective" deduction of categories? – It is an inquiry which shows that the only possible objects of knowledge a priori are appearances, because categories could not be conditions a priori of existence of things themselves anyway: we are not gods.

What is the "subjective" deduction of categories? – It is the proof a priori that the categories contain the conditions of possibility of appearances as the objects of possible perception or experience. In other words, subjective deduction is the tr. deduction of categories as such.

What is the "sufficient" deduction of categories? – It is the reduced version of subjective deduction. It shows that only perceptions which are connected in accordance with categories may be thought as having relation to a transcendental object. It is "sufficient" within the framework of that way of achievement of the goals of critical philosophy which set the tr. deduction as such aside and pays most attention to the metaphysical deduction, and also has some components a posteriori.

What is the "complete" subjective deduction? – It is an inquiry which is to prove that categories are not necessary conditions of thinking of objects only, but also that they are the grounds of possibility of perceiving these objects.

Has the "complete" subjective deduction any innere subdivisions? – It is divided into two stages. At first, Kant proves that categories have an a priori relation to the manifold of sense intuition in general, then - that they have the same necessary relation to the manifold of our intuition, space and, primarily, time. Such a devision is necessary because when there is still a possibility that categories could have objective validity on the manifold of our sense intuition only, then the risk of amalgamation of categories with the modi of our sense intuition is not to the end avoided, while the tr. deduction should confirm the very fact of non-sensual origin of the categories.