Metaphysics is the study of what kinds of things there and what they are like in the most general terms. We have both a common sense picture of the world and a scientific picture of the world, and sometimes these two appear to conflict. Part of the job of metaphysics is to try to adjudicate what, if anything, in our picture of the world needs to be given up. Central questions in metaphysics include:
Objects: Are there nonexistent objects? Can there be distinct identical objects? Can there be distinct objects in exactly the same place at the same time?
Time: How do objects persist through time and change? Do future and past objects exist? Does time flow and at what rate?
Persons: What constitutes our personal identity? Are we animals, souls, or something else? Does identity matter for persons to survive through time and change?