One finds in some rishonim the importance of Metaphysics. Mainly that would be Ibn Pakuda [author of the Obligations of the Hearts], Binyamin the doctor [author of Maalot HaMidot], Rambam and others. [They do not see this as bitul Torah [waste of time that should be used for learning Torah].] So while clearly they are referring to the discipline, still I would say the main reference is the Book Metaphysics by Aristotle.
So what does that mean for today? My impression is that this discipline has developed in three different directions. Kant (along the lines of Leonard Nelson); Hegel; G.E. Moore. That is I would not venture to say which of these is right because each school seems to have very great and important points. But not the whole picture.
[The Kant Friesian school tends towards reason in areas of physical reality. It is in spiritual reality it tends towards a sort of fifth sense [non intuitive immediate perception. While Hegel agrees totally with these realms of spiritual reality, he holds that reason can penetrate even there. The G.E. Moore School simply holds that that way that Hume limited the range of reason is just not so. So he is like Hegel.]
[So in philosophy it seems you have the Kant Fries school of Leonard Nelson. Then Hegel and then G.E. Moore. It is hard to know which one is correct, but all have something to add to understanding.
