A Priori Synthetic Judgments in Physics: Kant’s View
A Priori Synthetic Judgments in Physics
Analytical Concepts
The Understanding as a Faculty of Concepts: It is now possible to explain how synthetic judgments a priori are possible by analyzing another of the physical faculties of knowledge: understanding. Sensitivity and understanding are the two constituent phases of knowledge. Through sensitivity, we are given objects; through understanding, we can understand them.
We understand what something is when we can embrace that something under one concept. So, Kant says that understanding is the faculty of concepts.
Concepts of Experience and Pure Concepts: Understanding is the power of trials. Concepts can be of two types:
- Concepts of Experience: Made from sensory experience. With them, you can make judgments of experience. Such judgments do not interest Kant, but he says our understanding has other concepts that predate experience and are not just derived from it but make it possible. Such concepts impose an order on our impressions that would otherwise appear as chaos. This second type of concept is:
- Concepts a Priori: Not made from experience. According to Kant, the concepts of “cause” and “substance” belong to this type. For empiricists, these concepts are derived from experience. Kant believes that concepts such as these are not derived from experience. Kant countered by saying that if we perceive things as limited, it is because we apply the concept of limit, because objects are organized as delimited by sensitivity.
Classification of the Pure Concepts of Understanding: Understanding is our ability to judge, that is, to make judgments. According to their logical structure, trials may be of a dozen different types. Each type of trial is a specific intellectual function, which is what we call a category. In other words, each type of trial is a link between different representations, and each type of trial requires a different type of link, a separate category.
The Categories and the Fundamental Principles of Physics
Now we need to explain how fundamental principles of physics are derived from these categories. The problem is very complex and consists of two parts: first, that which Kant develops in Analytic of Principles, is to derive what he calls the fundamental principles of understanding from the categories and pure intuitions. The second part is to derive from these fundamental principles the fundamental laws of physics.
Analytic of Principles
The focus of this section is to explain under what conditions pure concepts or categories of experience may apply, which are determined by the principles of understanding and are:
- A category of quantity corresponding to axioms of intuition, whose general principle says: “All intuitions are extensive magnitudes.”
- A category of quality are the anticipations of perception, whose general principle says: “In all events, the real that is an object of sensation has intensive magnitude, that is, a degree.”
- A category of relation are the analogies of experience, whose general principle says: “Experience is possible only through a necessary connection of perceptions.” This principle is divided into three, one for each category:
- “In any change of phenomena, the substance remains, and the quantum of it neither increases nor decreases in nature.”
- “All changes are produced in accordance with the law that links cause and effect.”
- “All substances, insofar as we can perceive them as simultaneous in space, are in complete interaction.”
- A category of modality are the postulates of empirical thinking in general. They are:
- “What is consistent with the formal conditions of experience is possible.”
- “What is interdependent with the material conditions of experience is real.”
- “That whose interdependence with the real is determined according to universal conditions of experience is necessary.”
Phenomena and Noumena
Kant calls a phenomenon that which is given to sensitivity and therefore subject to the conditions of spacetime. Intuition is the manner in which sensitivity sees things and hears from them. But sensitivity operates with mathematical laws, that is, defining its objects from space and time, trimming them from these.
Kant called noumenon the thing-in-itself. He says that the noumenon is pure intelligibility. This concept is a concept that limits experience, though Kant will find access to the noumenal, not through speculative or theoretical reason, but through practical reason.
Transcendental Idealism and the Copernican Revolution
Kant argued that all previously developed categories of knowledge are realistic attempts to know reality in itself, external to the knower. Given this epistemological attitude, Kant believes that rather than the individual spinning around the object, it should be the object that spins around the individual. So, Kant believed that his theory of knowledge is a real sea-change with respect to the foregoing. And he presents himself as the founder of idealism.
But Kant argues for a transcendental idealism. This means that although the items ordered and allow reality to be known (time, space, and categories) are set by the subject, they serve only if they apply to experience. While Kant says that he is an empirical realist: it means that the content of experience is given through the senses, it comes from external reality to the subject.