[scoofy]

You cite the categorical imperative, that shows up in the Critique of Practical Reason, which I would happily suggest folks interested in philosophy.

To actually sit down an read the first Critique, though, you'll probably need to know a significant amount of background, and a lot of the conclusions on how the mind work are certainly inaccurate.

Again, the Critique of Pure Reason is (from my understanding in studying if for a year a very long time ago) a unification of empiricism and rationalism, and a rejection of idealism in a period when that was an active fight. This was a period when there were constant concerns about proving the existence of God.

Ultimately it's obviously an important book, but it's just not a very accessible book. If you take a class on it you'll likely be expected to read much of it, if not all, but to say I struggled with it is an understatement.