Spanish translation here
The best way of understanding what metaphysics is, is to understand what it is not. Metaphysics is not a specialized discipline; it is not a theoretical or practical inquiry that deals with a specific set of facts, or tries to change the world in a specific way. Every kind of fact and every kind of activity has some specialized discipline correlated to it. No matter what kind of facts you name, no matter how trivial, chances are that someone has written a doctoral dissertation on it — or will write one someday.