And so we arrive at the world of our first philosopher. Without doubt he was the best known Greek of his time. When Thales predicted an eclipse of the sun he was using methods the Babylonians had been employing for centuries. But had he left it there western culture might never have arisen. His prediction of an eclipse was not accomplished by Babylonian astrology, it was accomplished by the application of pure mathematics and the assumption of a rational world. The Babylonians knew that the number of lunar periods between that elapsed between eclipses of the sun was constant. This was a part of the fundamental library of astrological concepts. But the occasion of the eclipse was not. In other words, after a given number of lunar cycles an eclipse would be expected. As a matter of modern knowledge, the eclipse would actually occur, but there is a probability of one in six that it would be seen at any given locality. Still, there is a regularity involved and the Babylonians were aware of it. When the expected time came they looked for it as a sign from the God. The difference between their motivation and Thales' is that their reasoning began and ended with the whim of the god, while Thales reasoning began with the fact that the future would always mirror the past and that events would occur as they always have. In other words this implied a rational universe. The Babylonians had no such assumption.

Unquestionably, Thales was well versed in Egyptian geometrical methods. But when he questioned the problem of change he was invoking a new element of thought never before seen in the history of man. There is a sense of contradiction between change and rationality. In our world we do not experience rational change, we experience individual changes. They are episodic, unexpected. In a rational world changes arise out of laws, are determined by cause and effect. The rationality of the world cannot be determined directly from experience. The reason for this is that rationality in nature can only be found in generalizations. What is true is true, it therefore cannot be different from what it is. But the world is in constant turmoil. Thales said that everything changes from one thing to another. This is what modern science would call an empirical generalization. It is not part of experience, it is abstracted from experience. What can reason tell us of what is true in a world of constant change? What is consistent in such a world is the ubiquity of change itself. If the world is rational and therefore is within the power of man's understanding. And, if everything we experience in the world is constantly changing and thus cannot be known, does this make experience irrational? If that were true then experience would not be of this world. But this is not an answer. Experience is not rational so if we assume that the world is, then it is necessary that we find an explanation that will tie the changing world of experience to the eternal world, the unchanging world that we can know. We must explain change in terms of the unchanging. Religions, that is all religions from that of the Homeric Gods to modern Christianity, deal with individual actions not with generalizations. They provide doorways to The irrational. The ultimate doorway being divine intervention.

In Homer's day divine intervention involved direct interaction by the Gods, sometimes as divine powers, in the lives of individual actors. It represented an irrational view of the nature of the divine. But, when Thales said that everything was filled with gods, he was expressing a physical condition of the world as well as a religious truth. Thales was a theologian as well as a philosopher. However, he made the Gods a mechanism of the universe and not the authors of change. The Gods, dealing as they do with individual events in a changing world, are irrational. They cannot be a functioning part of a rational world. But, if change is not at the whim of irrational gods, then from where did it originate and what is its nature? Thales did not reject the existence and actions of gods in the events of the world. What he posed was a rational explanation of change. What he said was that forces within the world itself were the underlying causes of change in the world. The fact that these forces were activated by gods changes nothing.

On the other hand, it poses philosophical problems that would not occur in an irrational world. Certainly invoking the law of parsimony would lead one to chose irrational Gods over rational forces. Intervention by the Gods is without question a much simpler way of describing the myriad events that occur in the world. Activated by gods or not, the idea that existence and change in the world grow out of rational forces within the world itself, that regardless of the role that the Gods play, basic emergence and change in the world occurs through natural forces was something new. Even more important was the idea that men have within their minds the ability to understand these forces. The mechanism by which men can come to know something about the truths of the world is called reasoning. The idea that men could understand their environment through reasoning was a new concept in the development of man, and it spelled the beginning of philosophy, of science, and of a new view of religion

Again, the problem that first presented itself to the Milesians was that of persistence and change. It may be true that individual changes could be more easily attributed to the Gods than to natural forces, but change itself, or persistence for that matter, is not a thing or event, it is a generalization. One implication of the assumption that change is through natural forces can be illustrated by this simple syllogism. All things change from one to another. Only those things that are made up of the same thing can change from one to another. Therefore all things are made up of the same thing.

The Babylonians and Egyptians had been using mathematical approaches for thousands of years but they never generalized from them making this one of the initial contributions of the Milesians; that is, the concept of generalization. It is also the basic concept underlying all of science. Generalization over time implies a rational universe. It implies that what holds today, at this moment, will also hold tomorrow, or the next century. At the same time, the concept of generalization carries with it its own baggage. The generalization of being is all that is. Therefore what is for this instant in time cannot change because change occurs only over time. That what is at this moment will be at the next requires an assumption of a rational universe.

Where does change originate? Either it is irrational, that is not understandable, or it is derived from forces within the world itself. If the world, to use the concepts available to the ancient Ionians, or the universe in our language, is all that is, then change cannot be caused by something else. Therefore all of the forces that cause and modulate change must be forces that exist within the world.

In the mind of a sixth century BC Greek, that which changes is living. Even in our modern world, we still consider change and motion two of the major characteristics of life. Rationally speaking, then, the most fundamental truths Thales and his followers discovered about the universe, were that everything that is must have been derived from a single substance that underlies the entire universe. This substance, being itself unchanging, was both eternal and divine. And the world as we know it came into being through change and motion within this underlying substrata itself. And finally, the universe itself is a living thing.

Thales then asked; which of the four elements, air, water, fire and earth, has the best claim to be looked on as the living and divine substance which generated the universe out of itself? We don't have a great deal of information about the ideas of our first philosopher, but there are two implications we can derive from what we do know. The first is that the world is rational. The second is that man has a peculiar faculty for understanding the world, his reason. Therefore it must be through reason and reason alone that the answer to this question would be found.

Hack brought out another point regarding Thales as a theologian. Since life and motion are one and the same to the ancient Greeks, the material source of all things, being in eternal motion, was alive. It is thus also the ultimate source of all life, making it both the cosmogenetic god and the supreme God. Water is the source of all things that grow. Heat is produced and maintained by moist making water the source of fire. The seeds of all things are moist thus water is the source of all life. But this implies unlimited power .Power is what made a Greek god divine. Thales then came to the conclusion that the substrata out of which everything that exists in the world emerged was water. Hack came to a different conclusion, that water is therefore the ultimate God. Other than Hack, it is difficult to find any scholar who would take the step of making the underlying substrata of Thales a God. However, that it is divine is acknowledged by all. The step that Hack took to calling it the Cosmogenetic and Supreme God probably reflects later and more developed concepts onto the work of the early Milesians. However, the ingredients are there whether the Milesians took the step or not.

Reason told the Milesians more than that there was an underlying substratum out of which all of the world must have been created. It also told them that it must contain within itself the cause of both motion and change, and it must be of the same nature as the psyche or the soul. Not only that, but while it is the source of all change, it must be everlasting, never changing. This is what they meant when they said that it must be divine.

It is not just religion and philosophy that Thales is noted for. He is also considered the father of science. One story told about him was that one year he predicted in advance that there would be a bumper crop of olives. He then leased all of the local olive presses and made a killing on the olive oil market.

Thales introduced geometry into the Greek sphere. He used fundamental geometric the Egyptians used to measure the height of pyramids, to measure the distance to ships at sea. He developed a description of the world as floating on water. To be more accurate, Burnett said that we should consider that the greatest feat of Thales was the application of generalizations on mathematical practices developed by the Egyptians.

It is when he adapted these generalizations to the explanation of change in the world that Thales once and for all placed his own stamp on western culture. Nothing that changes can be known because as soon as it is known it changes into something else. That which is real, that can be known, is that which never changes. Thus change itself cannot be known. However, in a rational world in order for there to be change there must exist some thing that is changing. Some thing that must exist in order to change but cannot be known because it is constantly changing. Since what is real is what can be known, what is real cannot be changing. It must be that which lies beneath change itself. In other words everything is changing from one thing to another while the common element out of which all things are made at all times remains constant. Thus this common element, the substrata of the universe, called the Arche by the Milesians, is real, eternal, divine, and the source of all change.

These things cannot be known directly through experience because experience is rooted in change. But they are nonetheless undeniable because we do experience. That everything changes is obvious to anyone. Either this change is the result of irrational Gods or through a rational nature. Which you choose is up to you, neither can be proven. Once Thales and his followers had chosen the route of rationality the conclusion of the constant substrata became a necessary truth. Thales called it water, Einstein called it the unified field. It is the ultimate conclusion of the rational thinker. Hack used the term "Cosmogenetic God" implying that it was the religious as well as the rational source of the universe. Though it is highly unlikely that Thales would have put it that way, and certainly Einstein would not, it is nevertheless the best description that can be applied to the idea of the "Arche" as seen by both. Consider that both Thales' Arche and Einstein's unified field contain within themselves the source of all motion and change and that both are the formal unchanging source of the universe. The road from Thales to Einstein is a long one and we will follow it but it was Thales who took the first step.