Who am I? This question continues to trouble us. The somewhat cryptic three-word sentence breaks up into various queries: What kind of being am I? What essential features do I share with animals or with other human beings? What differentiates me from them? What or who is this thing now sitting or writing this introduction, thinking these thoughts? Why do I often experience myself as a single subject of experience, or believe myself to be an autonomous agent capable of causing changes in the world, but at others feel a divided and inconsistent creature, or a powerless slave of circumstances? Do those experiences reveal anything about my true nature? What in the midst of all this is particular only to me, as this one individual, this person with these thoughts, likings and personal characteristics?

For a long time, the notion of self was considered to be accompanied by ontological commitments that scholars with a physicalist and scientific world-view could hardly entertain. But there is still no escape from these questions. Even though they may ultimately lead to different kinds of inquiries about, for instance, the essential nature of human beings, personal identity, rational agency, etc., and even if many of these issues would be best approached from a third-person rather than a first-person perspective, they still have one aspect in common: they are all, broadly speaking, reflexive. They are all questions that the inquirer asks about his or her own nature.