- Explain Kant's investigation of knowledge in relation to Hume's account of experience and certainty.
- Distinguish sensory input from the conceptual organization required for knowledge.
- Explain the roles of space, time, concepts, judgments, synthesis, and unity of consciousness.
- Connect rational agency with freedom, setting ends, consent, and the humanity formula.
- Apply Kant's universal-law test to the supported example of broken promises.
Kant's Critical Project and Hume's Challenge
Kant organized his philosophical project around what one can know, what one should do, and what one may hope. The Critique of Pure Reason investigates what can be known objectively and with certainty about the world, the self, and their relationship.
Kant sought a secure foundation for scientific knowledge by bringing reason and sensory experience together.
What did Hume argue repeated observations can and cannot establish?
Repeated experience may increase the expected chance that an event will recur, but repeated observations do not provide certain proof of recurrence.
Pure Reason and the Sources of Knowledge
The Critique of Pure Reason argues that knowledge requires both sensory input and conceptual organization. Reason shapes sensory data by formulating concepts, while the understanding orders and shapes sensory material through its own a priori modes of operation.
In Kant's account, would sensory input without conceptual organization satisfy the stated requirements for knowledge? Explain.
No. The Critique of Pure Reason argues that knowledge requires both sensory input and conceptual organization.
Space, Time, and Mathematics
- Experiencing an object as separate from oneself requires placing it in space.
- Recognizing that one event follows another presupposes temporal order.
Pure intuition enables a perceiver to distinguish a particular unit of space or time within a totality. The ability to construct repeatable units makes addition, multiplication, subtraction, and division conceivable.
Which condition is presupposed when one recognizes that one event follows another?
Temporal order is presupposed.
Concepts, Judgments, and Categories
Concepts focus, select, and organize the flow of experience. They have no content of their own and require experiential material to organize.
- Quantity
- Quality
- Relation
- Modality
What does a judgment do with diverse representations?
It unifies them into a more complex representation of an object.
Synthesis and the Unity of Consciousness
Kant treats synthesis of differentiated parts into unities as necessary for thinking. The act of focusing synthesizes selected experiential material into a unity.
- Experiential understanding separates phenomena into parts and recombines selected parts into wholes.
- Constructing concepts from experience requires memory and imagination.
- Previous representations must be recognized as related to present ones for a unified representation to arise.
What relationship between previous and present representations is required for a unified representation to arise?
Previous representations must be recognized as related to present ones.
Moral Reason, Freedom, and Humanity
Kant extended his investigation from theoretical reason to practical reason governing action. He sought a pure moral code that does not depend on anything external to rational agency.
Kant connects the capacity for reason with freedom and identifies humanity's distinguishing capacity as the ability to set ends for oneself.
According to the stated account, what capacity is disrespected when people are used for one's goals without their consent?
Their capacity to set their own ends is disrespected.
The Categorical Imperative and Kant's Influence
Kant's universal-law principle permits only maxims that one could will as universal laws. One test asks whether universalizing a maxim would produce a contradiction in conception.
A further test asks whether the agent could rationally will the universalized maxim for oneself and others. The humanity formula requires actively supporting other people's pursuit of their ends.
Paul Guyer says that Kant's requirement to treat humanity as an end has gained wide acceptance in modern moral thought and philosophy. Kant's focus on the relationship between experience and conceptual thinking helped initiate German idealism.
What relationships among rational beings' ends are required in a kingdom of ends?
Their ends must be mutually consistent, harmonious, and reciprocally supportive.
Common misconceptions
Watch out: Repeated observations establish with certainty that an event will recur.
Instead: Hume argued that repeated observations do not provide certain proof of recurrence, although repeated experience may increase its expected chance.
Watch out: Concepts supply their own experiential content.
Instead: Concepts have no content of their own and require experiential material to organize.
Watch out: The combination involved in synthesis is given by objects.
Instead: Kant holds that combination is performed by the subject rather than given by objects.
Watch out: The humanity formula forbids every use of another person as a means.
Instead: Kant's humanity formula requires treating humanity always as an end and never merely as a means; using people for one's goals without their consent fails to respect their capacity to set their own ends.
Lesson recap
- Knowledge requires both sensory input and conceptual organization.
- Space and time are preconditions for sensory experience in Kant's account.
- Synthesis of differentiated parts into unities is necessary for thinking.
- The humanity formula requires treating humanity always as an end and never merely as a means.
- The universal-law principle permits only maxims that one could will as universal laws.