This document provides an introduction to philosophy, discussing its definition, nature, and functions. It defines philosophy as the love of wisdom, connecting it to both intellectual pursuits and passionate engagement. It describes three key characteristics of philosophical activity: (1) addressing the widest generalizations and big questions, (2) focusing on fundamentals and root causes that explain other areas of knowledge, and (3) striving to integrate different areas of thought into a coherent whole. It uses the example of the ancient Greek philosopher Thales to illustrate these three traits of philosophical work.