Disagreed with the Sophists' contention that there is no objective truth but only subjective opinion. Socrates believed that by examining a number of individual manifestations of a principle or concept, the general principle or concept itself could be defined clearly and precisely. These general definitions were stable and knowable and, when known, generated moral behavior. The technique used by Socrates that examined many individual examples of a concept to discover what they all had in common. Considered the father of modern medicine because he assumed that disease had natural causes, not supernatural ones.
Health prevails when the four humors of the body are in balance, disease when there is an imbalance.
The physician's task was to facilitate the body's natural tendency to heal itself. Argued that all mental and physical disorders had natural causes and that treatment of such disorders should consist of such things as rest, proper diet, and exercise. Proposes a completely materialistic universe wherein everything consists of atoms. Offered atoms as the physis. Everything in nature, including humans, was explained in terms of atoms and their activities.