In the age of Leucippus and Democritus, and even
before them, lived those called Pythagoreans, who
applied themselves to the study of mathematics and
were the first to advance that science; and, penetrated
with it, they fancied that the principles of mathematics
were the principles of all things.
—Aristotle, Metaphysics A.5
Lysis woke up abruptly, his heart thumping, his forehead covered with sweat. He had been dreaming of fire—again. Only this time the dream had seemed so real he could have sworn he had felt the scorching heat on his face and heard the screams, people yelling as if in pain, crying for help. He was an optimist by nature, used to looking at the bright side of things, but lately he had become possessed with a feeling that those dreams forebode some imminent calamity. The time was the second year of the 71st Olympiad, or 495 BC.
Could my dreams be a warning from the gods? He wondered. It was a while since he had sacrificed to Hera, the queen of the Olympian gods. When he worshipped at her temple situated in a promontory overlooking the Ionian Sea near the city of Croton, in Magna Graecia, he would leave wheat and barley and cheese cakes as offerings. He knew that the cow was the animal especially sacred to the goddess, but the killing of animals was forbidden in the fraternity— the sect, as outsiders called it—as was the eating of animal flesh. As prescribed by the Master, he would enter the temple from the left and wearing a clean garment in which no one had slept, because sleep, just