Kant’s Metaphysics, Science, and Knowledge Theories
KANT: Metaphysics and Science
According to Kant, for a trial to be considered scientific, it must meet two conditions: increasing our knowledge and possessing necessary and universal validity. This validity cannot come from experience, as it is changing and provides only likely generalizations. Scientific judgments must be synthetic a priori judgments, where the predicate is not included in the subject (unlike analytic judgments) and provides new connections.
Mathematics deals with space and time. Geometry analyzes space, arithmetic analyzes time. Since space and time are conditions for phenomena, their properties are transmitted to any phenomenon occurring within them. Thus, mathematical knowledge is universal and necessary, as all phenomena exist in space and time. Synthetic a priori judgments are possible in mathematics and natural sciences because they are based on categories.
We cannot know objects as they are in themselves (noumena), only as they appear to us through transcendental structures of feeling and understanding (phenomena).
Kant considered dogmatic rationalist metaphysics (Wolff) when examining metaphysics’ possibility. Metaphysics is purely rational knowledge, independent of sensory data, attempting to liberate concepts from observational limitations.
Knowledge of things in themselves (soul, world, God) is impossible. These ideas unify our understanding of phenomena, but we cannot know them as we lack intuition, only perceiving phenomena.
Metaphysics is reduced to concept analysis, failing to reach reality. Metaphysics as a science is impossible, though there is a natural tendency to apply categories beyond sensitivity, seeking unattainable absolute knowledge.
Metaphysics retains a critical role, eliminating dogmatism, safeguarding morality and religion, avoiding speculation, and pointing out the limits of scientific knowledge. While metaphysical knowledge of reality through pure reason is impossible, it reveals the source of metaphysical error and drives humans to seek greater unity and coherence in knowledge.
Experience and A Priori Knowledge
Kant identifies experience with sensitive knowledge. Sensitivity and understanding have a priori transcendental forms, acting as templates for sensory data and concepts. Sensitivity and understanding shape reality.
Synthetic a priori judgments are possible because all knowledge begins with experience, though not all knowledge arises from it.
Impressions or sensations allow us to intuit objects. The subject unifies, organizes, and structures sensations, adding an a priori form to empirical elements. Kant calls what is given by the senses the matter of sensitivity, and the structuring element the form. Realism is overcome; the known object is not a sensory copy.
Analyzing knowledge content, devoid of understanding, leaves only sensitive knowledge. Removing elements of feeling leaves only the form of sensory knowledge, the pure form of sensibility.
For external objects (table, house), we can remove sensory representations (size, shape, color) but not represent them without space.
Space cannot be a thing, as things exist in space. If space were a thing, it would require another space to contain it, leading to infinite regress. Space is not an empirical concept; it is assumed in representing objects. Space is an a priori representation, independent of experience.
Kant identifies two ways of feeling: external sense (representing objects in space) and internal sense (awareness of psychic states in time). Space and time are a priori forms of sensation or pure intuitions. Phenomena, the objects of experience, result from sorting feelings (matter) in space-time (form). Mathematics constructs judgments about space (geometry) and time (arithmetic).
Understanding is the faculty of thinking about objects given in empirical intuition (phenomena). Thinking subsumes phenomena under concepts, providing unity and meaning. There are empirical and a priori concepts (categories), which are a priori structures of thought. Nature, as a set of phenomena, is subject to categories, the conditions for thinking about experience. Physical laws are imposed on experience by understanding, acquiring necessity and universality, enabling physical science. Physical laws are valid only for the phenomenal world.
Criticism of Traditional Metaphysics
Since there is no empirical corresponding to these ideas, forming images of smaller objects is impossible. Transcendental illusion occurs when reason improperly uses categories, applying them to these ideas as objects, leading to illusory and contradictory conclusions. This illusion is inevitable, rooted in reason’s essence.
There are three types: paralogisms (inferences about the soul), antinomies (inferences about the world), and the ideal of pure reason (inferences about God).
A paralogism is false reasoning. There are formal logical fallacies and momentous errors inherent in reason’s nature, which are unavoidable.
The soul is immaterial, a simple, incorruptible substance. Its unity and identity give rise to personality. These features, combined with its relationship to objects in space, make it the principle of life in matter. The transcendental doctrine of the soul is falsely regarded as a science of pure reason about our thinking being.
Antinomies
- First Antinomy: Thesis – The world has a beginning in time and is limited in space. Antithesis – The world has no beginning in time and is unlimited in space.
- Second Antinomy: Thesis – Any compound substance consists of indivisible parts. Antithesis – Any composite thing consists of simple parts, and nothing simple can exist.
- Third Antinomy: Thesis – Causality according to natural laws is not the only form; freedom is another. Antithesis – There is no freedom; everything happens according to natural laws.
- Fourth Antinomy: Thesis – A necessary being exists as part of the world or its cause. Antithesis – A necessary being must be absolute and cannot be part of the world or its cause.
In each antinomy, the thesis reflects the dogmatism of pure reason, while the antithesis reflects empiricism. Dogmatism affirms the unconditional, necessary, and free. Empiricism is grounded in experience.
In the third antinomy, there would be no contradiction if freedom were considered a phenomenon. Necessity applies to phenomena, freedom to things in themselves.
God is the sum of all positive predicates, conceived as an idea, not an experienced thing. God serves as a transcendent ideal.
The ontological proof states that a being with all positive properties must exist. Kant argues that neither subject nor predicate can necessitate existence; necessity exists only in analytic judgments.
The cosmological proof argues that if something exists, something absolutely necessary exists. Kant claims these proofs presuppose the ontological proof.
The physical proof is based on nature’s regularity, implying an intelligent creator. Kant argues this only suggests a cosmic architect, not a perfect being. The proofs for God’s existence are invalid, but refuting Kant is also impossible.
Reason’s ideas lead to metaphysical illusions, which are not errors but misuses. Images can be used constitutively (leading to illusion) or regulatively (guiding knowledge).
Theory of Knowledge
Kant’s “Copernican revolution” reverses the roles of subject and object in knowledge. Knowledge’s necessity and universality cannot come from experience. Objects must adapt to our knowledge, not vice versa. Understanding is not passive but actively shapes reality.
Unlike rationalists and empiricists, Kant posits that knowledge results from the collaboration of reason and experience. Sensitivity provides intuitions, understanding provides concepts.
Intuitions without concepts are blind; concepts without intuitions are empty.
Concepts are either empirical (from experience) or pure (categories, a priori). Categories are structures from which empirical concepts are generated, enabling judgments.
Thinking is making judgments. All acts of understanding can be reduced to judgments, revealing the categories at work. This is the transcendental deduction of categories.
Reason is the supreme capacity for thinking, producing reasoned trials. Reason seeks general principles to cover phenomena, searching for the unconditioned (the ultimate principle underlying all phenomena).
There are three transcendental ideas: soul, world, and God. These ideas unify phenomena but offer no knowledge as they lack intuition.
Objects are divided into phenomena (objects as perceived through transcendental forms) and noumena (things in themselves, beyond our reach). Only phenomena can be known.