Immanuel Kant 
Kant: Groundwork of the Metaphysics of Morals 

Kant’s Groundwork of the Metaphysics of Morals is one of the most important works in modern moral philosophy. It belongs beside Plato, Aristotle, Machiavelli, and Hobbes. Here Kant sets out to articulate and defend the Categorical Imperative — the fundamental principle that underlies moral reasoning — and to lay the foundation for a comprehensive account of justice and human virtues.