Political philosophy of Immanuel Kant

Immanuel Kant was a very famous philosopher who lived around 300 years ago. He thought about lots of different things, but his most famous idea was that people should always do what is right no matter what. Kant said that actions should be judged by whether they correspond with a certain set of moral rules that he thought up. He thought that acting on rules like this is the only way to truly be moral - and he called this idea the "categorical imperative". So basically, Kant believed that you should make moral choices based on following a specific set of moral rules - not just because it's what people around you think or what you personally want.