The Critique of Practical Reason - Original Version With Bonus Annotations For Kindle [Annotated] [Format Kindle]

This version also includes annotations on:

- information on the historical context of the book
- detailed biography of the author
- literary critique

The Critique of Practical Reason is the second of Immanuel Kant's three critiques, first published in 1788. It follows on from his Critique of Pure Reason and deals with his moral philosophy.

The second Critique exercised a decisive influence over the subsequent development of the field of ethics and moral philosophy, beginning with Fichte's Doctrine of Science and becoming, during the 20th century, the principal reference point for every moral philosophy of a deontological stamp.

Kant sketches out here what is to follow. Most of these two chapters focus on comparing the situation of theoretical and of practical reason and therefore discusses how the Critique of Practical Reason compares to the Critique of Pure Reason.

The first Critique was a critique of the pretensions of pure theoretical reason to attain metaphysical truths beyond the ken of applied theoretical reason. The conclusion was that pure theoretical reason must be restrained, because it produces confused arguments when applied outside of its appropriate sphere. However, the Critique of Practical Reason is not a critique of pure practical reason, but rather a defense of it as being capable of grounding behavior superior to that grounded by desire-based practical reasoning. It is actually a critique, then, of the pretensions of applied practical reason. Pure practical reason must not be restrained, in fact, but cultivated.

Kant informs us that while the first Critique suggested that God, freedom, and immortality are unknowable, the second Critique will mitigate this claim. Freedom is indeed knowable because it is revealed through the force of the moral law. God and immortality remain unknowable, but practical reason now requires belief in these postulates of reason. Kant once again invites his dissatisfied critics to actually provide a proof of God's existence and shows that this is impossible because the various arguments (ontological, cosmological and teleological) for God's existence all depend essentially on the idea that existence is a predicate inherent to the concepts to which it is applied.

Kant insists that the Critique can stand alone from the earlier Groundwork of the Metaphysics of Morals, although it addresses some criticisms leveled at that work. This work will proceed at a higher level of abstraction.

While valid criticisms of the Groundwork are to be addressed, Kant dismisses many criticisms that he finds unhelpful. He suggests that many of the defects that reviewers have found in his arguments are in fact only in their brains, which are too lazy to grasp his ethical system as a whole. As to those who accuse him of writing incomprehensible jargon, he challenges them to find more suitable language for his ideas or to prove that they are really meaningless. He reassures the reader that the second Critique will be more accessible than the first.

Finally, the sketch of the second Critique is presented in the Introduction. It is modeled on the first Critique: the Analytic will investigate the operations of the faculty in question; the Dialectic will investigate how this faculty can be led astray; and the Doctrine of Method will discuss the questions of moral education.

To be an object of practical knowledge, as such, signifies, therefore, only the relation of the will to the action by which the object or its opposite would be realized; and to decide whether something is an object of pure practical reason or not is only to discern the possibility or impossibility of willing the action by which, if we had the required power (about which experience must decide), a certain object would be realized.