Immanuel Kant: Philosophy of Knowledge and Morality
Immanuel Kant (18th Century)
Immanuel Kant, a German (Prussian) Enlightenment philosopher, is considered by many thinkers as both a culmination of previous philosophical traditions and a starting point for new ones. Kant undertook a rigorous scientific study of all preceding philosophy, while simultaneously laying the groundwork for a new philosophical era. His work represents a Copernican revolution in philosophy, similar to Copernicus’s impact on astronomy. This revolution marks a turning point in human knowledge: the conditions of knowledge are not determined by the object but by the subject. These conditions are a priori structures or elements provided by reason. These conditions, such as time and space, are independent of experience and are used to organize our perceptions. While we perceive things through our senses, we wouldn’t be able to understand them without these pre-existing structures of reason. For Kant, human reason has two distinct uses:
- Theoretical/Speculative: Involves the construction of science (universal).
- Practical: Involves the construction of morality (universal).
Kant believed that if everyone possessed a universal morality and used reason to establish what is good, we would be self-sufficient, perpetually at peace, and wouldn’t need external guidance. He argued that time and space are not objective realities but rather subjective tools used to organize our experience. Time, in particular, is not objective because it is relative to speed; time varies depending on one’s velocity.
The Problem of Knowledge and Morality
In his Critique of Pure Reason (1781), Kant explores the theoretical/speculative use of reason in constructing science. In the Critique of Practical Reason (1787), he examines its practical use. Kant famously states, “All knowledge begins with experience, but not all knowledge arises from experience.” This signifies that some knowledge originates from reason itself. He unifies empiricism and rationalism, arguing that we acquire knowledge through both senses and reason, and that both are necessary for verification. We know something when our sensory perceptions are explained by reason. The senses provide the content of knowledge, while reason provides the a priori structures that shape and give meaning to this content.
Levels of Knowledge
1. Sensitivity: This level yields the phenomenon, the object of experience. To understand it, we need both senses and reason. Our senses provide sensations, which are meaningless on their own. However, the structures of time and space organize these sensations, allowing us to experience them. The phenomenon (that which we can place in space and time) contrasts with the noumenon (the “thing-in-itself,” which we cannot experience because it exists outside of space and time). Space and time are not objective realities but subjective structures used to organize and understand reality. They are also called ‘sensitive intuitions’. Sensitivity is passive because it receives the phenomenon.
2. Understanding: At this level, the understanding thinks about or judges the phenomena produced by sensitivity. It applies categories, which are a priori structures (pure concepts of reason), to the phenomena, resulting in an opinion or object of knowledge. Pure concepts are laws without content that can be applied to any given structure to create coherence. Examples include: chance, disjunction, conditional necessity, and possibility. These structures do not originate from experience. Judgments can be descriptive or evaluative (but not moral or legal). Understanding is active because it thinks about and makes judgments about the phenomenon. Imagination acts as a bridge between sensitivity and understanding, allowing the phenomenon to pass from sensation to knowledge.
3. Reason: At this level, there is no knowledge in the same way as in the previous levels. Reason performs the supreme synthesis, unifying all phenomena structured by understanding and referring them to something primary and unconditional: the transcendental ideas of the self, the world, and God. Reason seeks the ultimate meaning of things, postulating the existence of the self, the world, and God. In his Critique of Pure Reason, Kant questions whether metaphysics can be a science like mathematics or physics. He introduces two key concepts:
- Transcendental Aesthetic: Explains sensitivity and how mathematics is a science. Science, according to Kant, consists of propositions or judgments that are both universal and necessary, and provide knowledge independent of the subject. He distinguishes between analytic judgments (relations of ideas) which are universal and necessary but don’t provide new knowledge, and synthetic judgments (matters of fact) which provide new knowledge but are not universal and necessary. Kant argues that true science requires synthetic a priori judgments, which are grounded in experience but have their foundation in reason. Mathematics and physics exemplify this.
- Transcendental Logic: Explains understanding and why physics is a science. It is divided into Analytic (explaining understanding) and Dialectic (explaining reason). Kant concludes that metaphysics is not a science because it cannot make synthetic a priori judgments. Metaphysics deals with the self, the world, and God, which are beyond space and time, making the categories of understanding inapplicable. However, Kant argues that metaphysics has two important roles: a positive role in driving human inquiry, and a negative role in setting the limits of human knowledge.
How Should Man Behave?
Kant believes that man should act in accordance with the law derived from reason. He distinguishes between maxims (subjective principles) and laws (objective and universal mandates). The supreme law is the Categorical Imperative, the law of pure practical reason. Kant’s morality is formal, not material.
Material Morality: Focuses on content, defining a supreme good and prescribing actions to achieve it. It lacks moral autonomy, relying on external authority. It is hypothetical and a posteriori, based on observation of good and bad.
Formal Morality: Lacks specific content, ultimate good, or rules. It dictates how we should act based on reason, allowing for freedom and autonomy. It is categorical, necessary, and a priori, derived from reason. Kant identifies three types of actions: 1) actions against duty (illegal and immoral), 2) actions in accordance with duty (legal but amoral), and 3) actions from duty (legal and moral). True goodness, for Kant, lies in having a good will, guided by duty and respect for the law derived from reason. Formal morality postulates freedom, the immortality of the soul, and God.