"An Outstanding Mediocrity"
A near-contemporary of Plato, Mediocrates was a fourth-century BCE Athenian philosopher best-known for his controversial teaching that one should avoid all extremes.
Mediocrates apparently taught that a balanced life requires conscious effort to avoid standing out from the norm: in fact, the deliberate avoidance of all extremes, even extremes of virtue. In this, he differs from virtually all of his contemporaries, from whom the pursuit of aretê, “excellence”, was the ultimate goal of life.
For his doctrine of deliberate non-striving, he came to be known as the “Philosopher of the Middle”; indeed, his very name itself may be translated “halfway up the mountain.”
If Mediocrates wrote down his teachings, none of his writings have survived. He is, however, credited with originating a number of common sayings, including “Keep your head down,” “Just go with the flow, man (voc. ἄνερ, áner),” and "The higher up the tree the monkey goes, the more of its bottom you see."
According to the only known story about Mediocrates, a student of Aristotle once quoted him in the course of a debate.
“Who?” replied Aristotle.