A concern with ethics arises naturally from the moral problems we face in everyday life. The philosophical study of ethics addresses such questions directly. It also places them in a wider context, by examining questions like what, in general, makes an action good or bad, or what do we mean when we say that someone has a right or an obligation to do something. Ethical issues are closely connected to those that arise in social and political philosophy. Philosophy is distinctive, however, in that one of its subjects is the nature of knowledge itself.
Epistemology is the branch of philosophy that tries to understand what is special about knowledge.
Scientific knowledge raises special issues of its own, so there is a field called the philosophy of science. Some questions about reality seem to lie beyond the scope of any natural or social science. The broadest and most fundamental issues of this sort are taken up in metaphysics. Metaphysics also tries to understand what causation is, what free will is, and how we can be free if our actions are ultimately caused by circumstances over which we have no control. Metaphysics is a close cousin to the philosophy of mind.