Day 16: What Can We Know?

•      Of Phenomena and Noumena

•      The Transcendental Ideas

•      Immanent and Transcendent Metaphysics

•      The CPR as an Experiment

•      Read Hume, Treatise, Part II, Bk. III, sections i and ii.

Of Phenomena & Noumena

•      CPR-B294-315; A248-249

•      Phenomena

•      Noumena, negatively defined: “a thing in so far as it is not the object of our sensuous intuition” (CPR-B307) .

•      Noumena, positively defined: an object of non-sensuous or intellectual intuition, that we cannot have (CPR-B307)

The Transcendental Ideas

•      God (subject matter of theology)

•      The World (subject matter of cosmology)

•      The Soul (subject matter of psychology)

Transcendental Ideas

•      Consider:

     All humans are mortal;

     all scholars are human;

     therefore, all scholars are mortal.

•      Something more general:

     All animals are mortal;

     all humans are animals;

     therefore, all humans are mortal.

•      What happens when we look for more and more generality?

Transcendental Ideas

•      For Kant, the search for the ultimate unity and the ultimately unconditioned leads to the idea of God (as the ultimate unconditioned unity).

•      The search for unity in the world of phenomenal objects leads to the idea of The World.

•      The search for unity in the thinking subject leads to the idea of Soul.

Immanent & Transcendent Metaphysics

•      Transcendent Metaphysics should not be done.  It goes beyond experience.

•      Immanent metaphysics is the only kind of metaphysics we can do; it is confined to principles grounded in experience.

The CPR as an Experiment

•      The Antinomies

•      The refutations of metaphysical proofs

•      Kant could interpret the above as evidence in support of his inversion hypothesis (i.e. his Copernican Revolution)