Practical Morality

Lore & Background

Kant initially did not plan a separate critique of practical reason. His first work, the Critique of Pure Reason (May 1781), was intended as a "critique of the entire faculty of reason," covering both theoretical and practical aspects to prepare for metaphysics. By the time he wrote the Groundwork of the Metaphysics of Morals in 1785, Kant had shifted his view, distinguishing between a critique of pure speculative reason (necessary for nature) and pure practical reason (which he initially thought less critical because "in moral matters human reason can easily be brought to a high degree of correctness"). A section titled "Transition from metaphysics of morals to the critique of pure practical reason" in the Groundwork reflected this interim stance. However, Kant changed his mind again, briefly planning an appendix for the second edition of the Critique of Pure Reason (announced November 1786) before abandoning it upon that work's April 1787 publication. Ultimately, he completed the new manuscript in June 1787, sending it to printers in Halle; it was published in December 1787 but listed as 1788.

In Their Own Story

The structure of the Critique of Practical Reason mirrors that of the first critique, comprising a preface, introduction, Doctrine of Elements, and Doctrine of Method. The Doctrine of Elements splits into an Analytic and a Dialectic. The Analytic establishes practical rationality, analyzing moral principles to show pure reason can drive action independently of empirical senses or feelings. It discusses the "object" of pure practical reason (the good) and non-empirical incentives called "motivating springs" (Triebfeder). Conversely, the Dialectic addresses the "exposition and resolution of illusion in the judgments of practical reason," tackling topics like the highest good and past philosophical errors that used it as a moral basis. It also integrates the existence of God and the soul's immortality as "postulates of practical reason." The final section, the Doctrine of Method, focuses on moral education and how to give pure practical laws access to the human mind.

Reader's Guide

In the Preface and Introduction, Kant compares theoretical and practical reason. He argues the first Critique restrained pure theoretical reason's pretensions to metaphysical truths beyond experience, whereas the second critiques applied or empirical practical reason. While the first work concluded God, freedom, and immortality were unknowable theoretically, the second mitigates this on practical grounds: freedom is revealed by the moral law, while belief in God and immortality becomes a requirement of practical reason as postulates. Kant asserts the Critique stands alone from the Groundwork, addressing specific criticisms like Pistorius's objection regarding the concept of the good. He dismisses reviews claiming his work is jargon or unintelligible, challenging critics to prove their meaninglessness or find better language. The Introduction outlines the structure: the Analytic investigates operations of the faculty, the Dialectic examines how it can be led astray, and the Doctrine of Method covers moral education.

Did You Know?

• Kant sent the completed manuscript to printers in Halle in June 1787, but it was listed as published in 1788 despite appearing in December 1787.
• In the Groundwork (1785), Kant argued that a critique of pure practical reason was less necessary than one for speculative reason because human moral understanding could easily reach correctness even among common people.
• The work is structured into an Analytic, which establishes principles and incentives, and a Dialectic, which resolves illusions regarding the highest good and postulates like God's existence.