The present study is based on the remarkable fact that in ancient philosophy, problems and solutions have developed across vast spatial and temporal distances as well as national boundaries, with a consistent internal logic. It explains this development through the philosophers' realistic engagement with the things themselves, to which they pose the problems and from which they derive the solutions. The study focuses on relevant texts from the pre-Socratics, Plato, Aristotle, the Stoics, and Plotinus, demonstrating how they progressively uncover the causal relationships in things, moving from material causes to immaterial, spiritual ones, and ultimately to human reason and a first transcendent cause (God). This investigation into causes was the origin of the sciences in the West, concerning the problems and their solutions.