At one point I took a copy of Berkeley's Principles from my father's library. That was the first philosophy book I read. I found it fascinating and wanted to read more philosophy.

Leibniz believed in freedom, both divine and human, and he thought that contingency was a necessary condition of freedom. That is, if an agent A acts freely when choosing X, then A's choosing X cannot be necessary. But there are some elements in his philosophy that seem to make contingency impossible.

The role of metaphysics in relation to other disciplines, whether philosophical or not and including the natural sciences, is thus a foundational role. Lack of clarity in the concepts of metaphysics implies lack of clarity in other disciplines - both theoretical and practical disciplines - employing those concepts or employing concepts that depend on those of metaphysics.

I would say I was a philosophical boy. Thoughts about 'identical stones' are the earliest philosophical thoughts I remember. But when I was a teenager I also thought about the more typical philosophical problems teenagers think about: the existence of god, the objectivity of morality, whether one can know that the external world exists.

Those who think that metaphysics is just misunderstood grammar will react to my giving metaphysics some place or another in the system of knowledge.

The huge majority of philosophers seem to think that including impure properties in the range of the quantifiers of the principle would make the principle trivial. I have argued that it does not.

Knowledge has the form of a tree, and since metaphysics is the most fundamental one of the theoretical disciplines, it represents the roots of the tree.