Immanuel Kant 
Fundamental Principles of the Metaphysic of Morals [EPUB ebook] 

The first of Immanuel Kant’s mature works on moral philosophy and remains one of the most influential in the field. Kant conceives his investigation as a work of foundational ethics, one that clears the ground for future research by explaining the core concepts and principles of moral theory and showing that they are normative for rational agents. Kant aspires to nothing less than this: to lay bare the fundamental principle of morality and show that it applies to us.