How Is Metaphysics In General Possible?

Unlike concepts of nature, metaphysics is concerned with concepts that necessarily cannot be given in experience, and therefore may not be falsified or confirmed through experience. Metaphysics must be concerned with reason itself. The concepts of the understanding differ from the concepts reason in that the former’s use is “immanent”, referring only to subjective experiences, while the concepts of reason extend to the universe of possible experiences, exceeding particular experiences and becoming “transcendent”. The concepts of reason are divided into three types: psychological, cosmological, and theological. These three concepts make up all of metaphysics.
1.) Psychological Ideas
“Pure reason demands that for each predicate of a thing we should seek its appropriate subject, but for this subject which is in turn necessarily only a predicate, we should seek its subject again, and so forth to infinity” (§46). From this it follows that we may never be able to attain a final subject. The substantial itself can never be thought; it is inconceivable. All the properties we use to cognize bodies must be effects of a lacking subject. We are unable to conceive a property other than as an effect of a force. This mode of thinking is responsible for the formulation of the “soul hypothesis”. There is thinking, so we assume there must be an underlying “thinker” to do the thinking. “For the I is not a concept at all, but only a designation of the object of inner sense insofar as we do not further cognize it through any predicate” (§46). The thinking self may be called substance, but if it is not proven to be persistent, the concept is empty and therefore useless. Persistence of the thinking self (soul) may be proven only in experience (when it obviously persists), but never after death (which is often the main concern).
2.) Cosmological Ideas
The cosmological idea “always finds its object only in the sensible world and needs no other world than that whose object is an object of the senses, and so, thus far, is immanent and not transcendent” (§50). None of the cosmological claims can be verified in experience because these ideas expand the conditioned with its condition making them impossible to be adequately experienced. There are four of these transcendent ideas, each containing two seemingly contradictory assertions which are each equally plausible through pure reason. The cosmological ideas (presented under §51) are as follows:

1. Thesis: The world has, as to time and space, a beginning (a boundary).
Antithesis: The world is, as to time and space, infinite.

2. Thesis: Everything in the world is constituted out of the simple.
Antithesis: There is nothing simple, but everything is composite.

3. Thesis: There exists in the world causes through freedom.
Antithesis: There is no freedom, but everything is nature.

4. Thesis: In the series of causes in the world there is a necessary being. Antithesis: There is nothing necessary in this series but in it everything is contingent.

What Kant calls “the strangest phenomenon of human reason” is that, when we think of appearances as things in themselves, which is most often the case, an “unexpected conflict comes to light” when we realize that both the theses and antitheses may be proven true. Reason seems to contradict itself. Each of these antinomies result from a misunderstanding according to Kant. The error made in #1 is considering space and time as things in themselves. As Kant has already established, space and time are merely intuitions, or forms of our understanding. Space and time do not exist outside of experience. The error made in #2 is in considering composite things and the parts they are made of as things which may be cognized outside of experience, which is impossible. In #3, it is a mistake to believe that causal necessity and freedom are contradictory. Causal necessity and freedom may both exist, because they refer to different things. The laws of nature, as Kant has established, refer only to appearances in space and time. The concept of freedom lies outside causality, so it can not exist in experience, and consequently it applies only to things in themselves. It is this same type of error which contributes to what seems like a contradiction in #4. Causal connections may be contingent in appearance, but the underlying things in themselves may have necessary connections.
3.) Theological Idea
This last idea is the ideal of pure reason. This is the idea of a supremely perfect first being (God). Kant believes any proof of this being is impossible, and therefore the efforts of any philosopher to attempt this feat were useless.


It seems to me that Kant takes the distinction between appearances and things in themselves a little to far in certain respects. Certainly these two types of things are different, but are they not at all constrained to one another? How is it that the appearance of something may be contingent but the thing in itself necessary. If all the things in themselves were necessary, how could the appearances be contingent? Could the appearances fluctuate while the things in themselves are stable? If it were the case that the appearances do not directly, necessarily correspond to the state of the thing in itself, there would have to be another factor at work here, it would not be merely an appearance of the thing in itself. Appearances certainly seem to be contingent, but if things in themselves were necessary, appearances would be as well, but then again both may be contingent. I believe that for an appearance to be an appearance of a thing in itself, it must directly correspond to the thing in itself, that is, not necessarily to resemble the thing in itself, but that for each thing in itself there is a single necessary appearance for it.