Immanuel Kant was a German philosopher who is widely considered to be a central figure of modern philosophy. Groundwork for the Metaphysics of Morals is one of the most important works of moral philosophy ever written. 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. In the text, Kant provides a groundbreaking argument that the rightness of an action is determined by the character of the principle that a person chooses to act upon. Kant thus stands in strong contrast to the moral sense theories and teleological moral theories that dominated moral philosophy at the time he was writing.