Socrates: A Man for Our Times by Paul Johnson Page A

in tension: everything is in conflict and tension, and this is the principle of universal stability, an argument often described as the first example of a priori reasoning in science. He was aware of the sheer size of things and introduced terms for “unlimited” and “the infinite.” But his follower Anaximenes rejected the water explanation and substituted air, which when dense became fire or winds or clouds and was subject to condensation. Another Easterner, Heraclitus of Ephesus, expanded the tension theory, noting that this was exactly how the bow and the lyre worked, an example of the close observation and shrewd deductions of which these early Greek philosopher-scientists were capable. To him, the principle of tension was signified by the logos , the symbol of eternity. It was also transcendent wisdom and the elemental fire. He was of royal blood but gave over the throne to his brother so he could write his Treatise , dealing with the logos . A fragment reads:
God is day and night, winter and summer, war and peace, plenty and famine, all the opposites which sustain things. Men are foolish creatures who must subject themselves to the logos or law. . . . The people must fight for the law, as for a defensive wall, for all human laws are nourished by the divine, which is one.
    He also wrote: “We ought to grasp that war is common and natural, as is justice which is strife, that all things come about in accordance with strife and what must be.” His best-known saying is “You cannot step twice into the same river.” But what does it mean? In antiquity he was known as Heraclitus the Obscure. When Euripides gave Socrates his works, Socrates commented, “What I understand is splendid. What I do not understand may be good too. But it would take a deep-sea diver to get to the bottom of it.”
    On the other hand, there were the Greek seers who lived in what is now Italy and were later known as the Westerners. Parmenides and Zeno lived in Elea and were also called Eleatics. They were systematic arguers and were the first to produce the kind of consequential series of deductions that are still in use today in learned circles. Parmenides in particular invented and honed philosophic tools and reflected on the term to be —what can be known must be—and nothing else can be—all expressed in a poem set in hexameters, chunks of which survive. He was between fifty and sixty years older than Socrates. Democritus was Socrates’ contemporary, and his theory that the universe was composed of infinitely small, undifferentiated pieces of matter, which he called atoms, and that their changing positions produce the visible compounds of the world identified by our senses still holds good, in part at least. His work was typical of the way in which the early Greeks identified portions of truth, tension and atomism, for example, but mixed them with speculative ideas we find nonsensical. Democritus, for example, thought the soul was composed of fine, round atoms and was as perishable as the body. Zeno was a superb arguer but thought that, properly speaking, there was no motion and no plurality.
    The Greeks had the gift of seeing concrete substances in abstract terms—hence their mastery of geometry and their complex ideas about the universe, achievements certainly denied to the Egyptians and even, on the whole, to the Hebrews. The difficulty was that they possessed neither the instrumentation nor the knack of engaging in empirical investigations. They could observe, but they did not experiment, except by accident. Pythagoras began the systematic study of numbers and, among other innovations, introduced the number ten, and in due course his work became of incalculable value to science. But when Socrates was a young man and explored, as he later said, the limits of scientific knowledge, he could not see any way of pushing them further. The cosmos was mute. It could be seen but could not speak. Above all, it could not answer