Book Notes/The Metaphysics of Morals

The Metaphysics of Morals

by Immanuel Kant

"The Metaphysics of Morals" by Immanuel Kant is a foundational work in moral philosophy that outlines his ethical framework, distinguishing between duties and moral laws. Kant introduces the concept of the categorical imperative, which asserts that moral actions must be universally applicable and stem from rational will. The book is divided into two main parts: the Doctrine of Right, which addresses legal and political philosophy, and the Doctrine of Virtue, which focuses on personal morality and ethics.

19 curated highlights from this book

Key Insights & Memorable Quotes

Below are the most impactful passages and quotes from The Metaphysics of Morals, carefully selected to capture the essence of the book.

Act only according to that maxim whereby you can, at the same time, will that it should become a universal law.
The good will is not good because of what it effects or accomplishes, it is good because of its volition.
Always treat humanity, whether in your own person or in the person of any other, never merely as a means to an end.
Freedom is the only condition under which a rational being can be the author of a law.
A duty is an action that is necessary and can be done from respect for the law.
An action is morally good if it is done from duty, not merely in accordance with duty.
The moral worth of an action does not depend on the realization of the intended result.
To be moral is to act according to the dictates of reason.
The concept of duty is the foundation of all moral philosophy.
A good will is the only thing that is good without qualification.
The good will is not good because of what it effects or accomplishes, it is good in itself.
It is not enough to possess a good will; it must also be directed to what is truly good.
Duty is the necessity to act out of reverence for the law.
The moral worth of an action does not lie in the effect expected from it, nor in any principle of action that is based on the expected effect.
A rational being is one who, by acting according to his representation of laws, can be an author of universal laws.
Man is not merely a means to an end, but always at the same time an end.
All imperatives command, either hypothetically or categorically.
The categorical imperative is a universal law that must be followed by all rational beings.
Freedom is the only property of rational beings.