Practical Morality
A defense of pure practical reason against empirical pretensions, grounding behavior in moral law rather than desire.
The Critique of Practical Reason (German: Kritik der praktischen Vernunft) is Immanuel Kant's second major critique, published in 1788, often called the "second critique." Following his first critique, it serves as a foundational work on moral philosophy, expanding on themes from the Groundwork of the Metaphysics of Morals (1785). While Kant had previously established the groundwork for ethics, this 1788 text specifically aims to develop his account of the will as determinable by the moral law alone. It places his ethical views within the broader framework of his critical philosophy system and deepens exploration of concepts like the feeling of respect for the moral law and the idea of the highest good.
Quick Facts
- Primary proponent
- Immanuel Kant
- Antagonistic view
- Applied or empirical practical reason based on desire
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.
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.
More in Themes & Philosophy
Elsewhere in A Practical Guide to Evil
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