Possible Clues:

• Greek with a theorem
• Greek philosopher/mathematician
• Philosopher, on leaving, snakes around market
• Maths expert terribly hasty to obtain silver and gold -- source of profit foremost
• Mathematician vaguely toys with a graph
• Greek philosopher and mathematician, d. c 500 BC
• Greek philosopher and mathematician of sixth century BC
• Pray, as Goth murdered philosopher
• A sporty sort detains dreadful old woman philosopher