Kant’s Theory of Knowledge: Sensitivity, Understanding, and Metaphysics
Kant’s Theory of Knowledge
The problem of knowledge in Kant and the development of his thought:
Kant addressed the problem of knowledge by distinguishing between two schools:
- Sensitivity: This is passive and receives sensations.
- Understanding: This is active and structures reality from ideas and concepts.
While the latter might seem rational (suggesting no experience is necessary to know reality), Kant, influenced by Hume, understood that our knowledge cannot move beyond experience. He argued that non-experimental concepts of understanding are only applicable to experience.
Metaphysics and Scientific Knowledge
Kant questioned whether metaphysics could be regarded as scientific knowledge, noting key differences:
- Science progresses, while metaphysics does not.
- Scientists generally agree on solutions, while philosophers constantly debate.
He then asked how science is possible, suggesting it relies on certain conditions:
- Terms of thumb: A posteriori, individual, and derived after experience.
- A priori conditions: Capabilities that precede experience and enable us to know its contents.
To determine whether these conditions are empirical or a priori, we must analyze trials:
- Analytical and a priori trials: Universal and necessary.
- Synthetic and a posteriori trials: Contingent and private.
Hume quoted these judgments, and Kant accepted the existence of synthetic a priori judgments, as in mathematics, which provide new information and are yet universal.
Finally, regarding the principle of causality, Hume argued that it is contingent and a posteriori, whereas Kant believed it was universal and necessary.
Critique of Pure Reason
In the Critique of Pure Reason, Kant discusses the three faculties of the human psyche:
Transcendental Aesthetic
This studies the sensible conditions of knowledge, without which no one could know reality. Kant calls these transcendental conditions. Space (a priori form of external sensitivity) and time (a priori form of inner sensibility) are essential for any perception. These are also called a priori forms of sensation or pure forms.
Possibility of Synthetic A Priori Judgments in Mathematics
Mathematics are related to space and time, which are universal and necessary. Therefore, mathematics also possess these properties. All objects of experience are given in space and time, and so these objects will be subject to mathematical judgments. Therefore, mathematics is universal and necessary.
Intellectual Knowledge
The senses gather information from the surroundings, but this information must be understood. Understanding is achieved through key concepts that allow us to interpret reality. A phenomenon is understood when we are able to assign a concept.
Types of knowledge:
- Empirical (a posteriori): Derived from experience (e.g., house).
- Categories (a priori): From the spontaneity of understanding (e.g., substance, causation, existence). There are twelve types of categories.
Research into the number of categories that constitute our understanding is called metaphysical deduction of the categories.
Elaborating on the theme, the categories are transcendental conditions of our knowledge. Phenomena cannot be conceived without the categories (they would be no more than a collection of disjointed impressions). In addition, the categories are useless without phenomena.