In the Preface to the second edition of the “Critique of Pure Reason”, Immanuel Kant compares his philosophy to the Copernican Revolution. It is said that as Copernicus believed that all heavenly bodies moved round the sun, Kant believed he was the center, and that everything moved around his philosophy. The philosophy of Immanuel Kant was so revolutionary because he brought together rationalism and empiricism. Because of Kant, the debate between rationalists and empiricists ended, and epistemology could move forward.Kant was inspired to build his philosophy after he encountered a copy of Hume’s “Inquiry”. He realized that he disagreed with many of the issues Hume brought up, and decided to refute them. In his book, “The Critique of Pure Reason”, he combined the ideas of Hume and the ideas of rationalists. Kant agreed with the empiricist claim that sense experience is the source of all beliefs, but disagreed with the conclusion that those beliefs may not necessarily be true. He also disagreed with the rationalist idea that truths about what does or does not exist could be decided through reason alone. He eliminated the debate by claiming that thinking and experiencing cannot let us know how things really are. Instead, Kant asked if it was possible that we have metaphysical knowledge. He claimed that the mind analyzes the data it perceives in terms of space and time. So, space and time are not features of external reality, as the empiricists and rationalists before him believed.