Critique of Pure Reason

Nonfiction | Book | Adult | Published in 1781

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Summary

Chapter Summaries & Analyses

Prefaces and Introduction

Part I: “Transcendental Aesthetic”

Part II: “Transcendental Logic,” Book I, Chapter I

Part II: “Transcendental Logic,” Book I, Chapter II

Part II: “Transcendental Logic,” Book II, Chapters I-II

Part II: “Transcendental Logic,” Book II, Chapter III

Part II: “Transcendental Logic,” Division II, Books I-II, Chapter I

Part II: “Transcendental Logic,” Division II, Book II, Chapter II

Part II: “Transcendental Logic,” Division II, Book II, Chapter III

Transcendental Doctrine of the Method

Key Figures

Themes

Index of Terms

Important Quotes

Essay Topics

Part II: “Transcendental Logic,” Division II, Book II, Chapter IIIChapter Summaries & Analyses

Transcendental Doctrine of Elements

Part II: Transcendental Logic, Division II: Transcendental Dialectic, Book II, Chapter III Summary

After tackling both the paralogisms and the antinomies, Kant comes to the third and final realm of dialectical illusions: the ideal. The ideal is a very important and noble concept. For Kant, the ideal is a specific kind of idea. Ideas are concepts of reason and therefore are not directly related to objective reality like the concepts of the understanding. Kant writes: “Ideas contain a certain completeness onto which no possible empirical cognition is adequate” (561). Kant discusses the importance of ideas in the philosophy of Plato. As concepts of reason that are only indirectly connected to experience, the idea surpasses any single experience of something of which we can have an idea. The ideal is the ultimate archetype of reason. “By ideal,” Kant writes, “I mean an idea not merely in concreto but in individuo, i.e., as an individual thing determinable or even determined by the idea alone” (560).

There are many ideals one can form, but the ideal of the most perfect being is the greatest of all: “The ideal of pure reason is the object of a transcendental theology” (570). Therefore, the ultimate ideal of reason is God. There are three methods of attempting to prove the existence of God through speculative reason: the ontological, the cosmological, and the physico-theological. Unsurprisingly, each of these proofs of God only provides an illusory account of his existence. Each proof fails in its own way. The ontological proof attempts to prove God’s existence form the concept of God. The cosmological proof attempts to prove God’s existence from the fact that there must be a cause of all things. The physico-theological proof attempts a proof of God by inferring it from the complexity and beauty of things in the world. Although Kant thinks these are noble attempts striving toward a worthy goal, Kant believes that all of them fail. Kant reveals the cosmological and the physico-theological proofs as complex versions of the ontological proof. The ontological proof fails because existence cannot legitimately be inferred merely from a concept. Existence can only be given in intuition. Since, all these proofs fail but God’s existence is still an important requirement for human flourishing, Kant advocates for a “regulative ideal” of God.

Part II: Transcendental Logic, Division II: Transcendental Dialectic, Appendix Summary

Kant ends his protracted elaboration of the “Transcendental Logic” with two notable appendixes: “On the Regulative Use of the Ideas of Pure Reason” and “On the Final Aim of the Natural Dialectic of Human Reason.” In the former Kant states that regulative principles, which are essential to the proper use of pure reason, should be consciously understood as maxims, not objective principles. Maxims, he writes, “are obtained not from the character of the object, but from reason’s interest concerning a certain possible perfection of the cognition of this object” (635). As such, they are subjective principles. Reason must be taken to be a basic power, or faculty, of the human mind.

The idea that reason is such a power is a regulative, subjective principle, not an objective fact. Reason is hypothetically understood as the power of the mind that infers unity and systematicity of experience. It is the great organizer of the world that (problematically) attempts to forge order out of chaos. Reason is the power to form regulative ideas of things. Kant discusses how one should understand the regulative idea of this power, i.e., the power to form regulative ideas. In short, this requires that we understand reason itself as a regulative idea that strives to create systematicity and unity to conscious understanding of the natural world. To articulate this, Kant develops maxims for reason’s explicit use.

In the latter appendix, “On the Final Aim of the Natural Dialectic of Human Reason,” Kant expands on the basic idea of the regulative use of reason but also includes some more determinate principles of reason. Kant writes that there are three basic subjective principles that reasonable actors hypothetically assume are true. In psychology, one should act as if there is a “simple substance” of the self. This is the idea of the soul. In cosmology, one should act as if nature is infinite. This is the idea of the world. Finally, in theology, one should act as if there is a God. This entails considering the “rational concept of God” (649). There is no possible way of proving the objective reality of these things. Still, reason requires these ideas for its proper dispensation. A formal principle of reason is that it regards “all arrangement in the world as if it had sprung from the intention of a most supreme reason” (650). This principle will provide the ground for reason’s attempt to elucidate the unity and systematicity of its world. Kant also reiterates the different kinds of human cognition and how they are related. Humans cognize objects via intuitions, concepts, and ideas, which correspond to the faculties of sensibility, understanding, and reason. Intuitions leads to concepts, which in turn form the basis of ideas. Reason operates on ideas, and thus only has a mediated relationship to sensible experience.

Part II: “Transcendental Logic,” Division II, Book II, Chapter III Analysis

The concept of the ideal is both important and intuitive. Kant defines the ideal as “an idea not merely in concreto but in individuo, i.e., as an individual thing determinable or even determined by the idea alone” (561). The idea is the concept of reason that has a certain adequacy, or completeness, that can never be captured by an empirical cognition. The ideal takes this concept and applies it to a specific, individual thing.

For instance, we might say that there is the actual, empirical breakfast, and then the ideal breakfast. The empirical breakfast might be a simple bowl of cereal or a piece of fruit and some toast. The ideal breakfast, though, could consist of the best tasting version of your favorite foods. It might also include time with good friends, your favorite coffee mug, the morning paper, extra time for relaxation, etc. There is a gulf between the empirical breakfast you ate and the ideal breakfast of your dreams. The ideal is the “most perfect of each kind of possible being” (561). This is a practically essential concept because it will always orient us toward what is best: “Just as the idea gives the rule, so the ideal serves in such a case as the archetype” (562). The ultimate ideal is, of course, God, the necessary being of which all the greatest powers are predicated.

Although the concept of the ideal is indispensable (and unavoidable) Kant also knows speculative reason cannot prove the existence of an ideal, especially God. In fact, given the nature of the idea (of which the ideal is a special type) its inexistence in outer reality is almost necessary. The ideal is a product of reason. It is produced by reason for reason’s benefit. Kant writes:

Hence the supreme being remains for the merely speculative use of reason a mere ideal–but yet a faultless ideal, a concept that concludes and crowns the whole of human cognition. Although the concept’s objective reality cannot be proved by this speculative path, it also cannot be refuted by it. And if there were to be a moral theology that can compensate for this deficiency, then transcendental theology–previously only problematic–proves itself indispensable (616).

In other words, Kant is not trying to prove that God (or any ideal) does not have objective reality. Instead, he is simply trying to show that all attempts to prove its objective reality fail. Instead, it must be taken on faith as a practical imperative of reason. Although we cannot prove that God exists, we must take this existence as necessary. It is through such an ideal that the proper regulation of human conduct in the word is harnessed and the potential for happiness transmuted. Far from crushing the value of reason in obtaining its goals, Kant wants to redirect our understanding of its goals. Kant wants to save reason from itself so that it can become the ultimate tool of human wellbeing.