What does it mean to be a thinking, perceiving, and feeling being, in short: a spiritual being? This is the fundamental question of the philosophy of mind. In this introduction, unlike typical presentations, the focus is not on the relationship between body and mind, but rather on the explication of our everyday understanding of ourselves as spiritual beings. What are mental states and processes, anyway? How can they be distinguished from other states and processes? And according to what principles can they be categorized into different types such as thoughts, perceptions, or sensations? Reflecting on these questions will clarify the central problems and positions of contemporary philosophy of mind.