Heraclitus

According to Heraclitus, all things are composed of fire. "This world," he says, "neither one of the gods nor of the human race has made; but it is, it was, and ever shall be, an eternally living fire." All comes from fire, and to fire all returns. "All things are exchanged for fire and fire for all, as wares for gold and gold for wares." Thus there is only one ultimate kind of matter, fire, and all other forms of matter are merely modifications and variations of fire. In his religious opinions Heraclitus was skeptical. But he does not, like Xenophanes, direct his attacks against the central ideas of religion, and the doctrine of the gods. He attacks mostly the outward observances and forms in which the religious spirit manifests itself. He inveighs against the worship of images, and urges the uselessness of blood sacrifice.