Heraclitus Suggested fire as the physis because in its presence nothing remains the same. He viewed the world as in a constant state of flux and thereby raised the question as to what could be known with certainty.
Hippocrates 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.
Imagination According to Aristotle, the pondering of the images retained from past experiences.
Inductive definition The technique used by Socrates that examined many individual examples of a concept to discover what they all had in common.