Ever since man first had the luxury of being able to sit and think as opposed to having to find food or fight off adversaries for most of his waking life, he has probably found himself occasionally looking around and wondering what exactly it is that he sees. The earliest Greek philosophers, a couple of hundred years before Plato, were concerned with such things as discovering the primary constituent of matter and the governing principles of the universe. They asked themselves: “What is the nature of the universe?”
Heraclitus is one of the better known, famous for his observation that the river that we step into for a second time is effectively not the same as the one into which we stepped the first time. The world has always and will always exist, he said, but “was ever, is now, and ever shall be, an ever-living Fire”, constantly changing. Things that appear to be opposites are really just extremes of a single thing, like the north and south poles of a magnet. Our phenomenal world is in a constant state of flux and the key to understanding it is introspection, looking inwards to find ourselves where there is stability and changelessness. “All things come out of one,” he said, “and the one out of all things; but the many have less reality than the one, which is God.” He was probably what we would now term a mystic and the few fragments of his writing that remain are obscure, to say the least! But these cryptic comments influenced later philosophers such as Hegel and Nietzsche, as well as others such as T. S. Eliot, whose wonderful poem ‘the Four Quartets” quotes him directly in several places.
A disciple of Heraclitus, called Cratylus, took the idea of continual change to its limits. He said that it was not even possible to hold a discussion since, by the time one came to answer a question, the person asking the question, the one answering and even the words and meanings would all have changed. So all he could do when asked something was wiggle a finger to indicate that he had heard… though whom he thought he was responding to is unclear.
Parmenides believed that our senses deceive us as regards the nature of objects. There are not many things but only the One, which is infinite and indivisible, present everywhere (and spherical!). He disagreed totally with Heraclitus, saying that there is never any change. There must be things, since we think of them and name them. Since we can do this at any moment, they must always exist. Conversely, it is simply not possible to think or speak of things that do not exist. The real always exists and is unchanging. That which changes must not exist and cannot be part of the real.
This is not an intuitive conclusion but, provides a very useful working definition of the word “real.” For something to be truly real, it has to exist always and never change. After all, if it changes into something different it cannot have been real can it? Conversely, when we see things changing, what we perceived must only have been a moving shape or form, like a dream and not truly real. This idea is a very important one.
Aristotle asked: if we do not understand the nature of reality, how can we know how to act? We could live our entire lives on the assumption that there is no afterlife for example, seeking self-gratification and ignoring the feelings of others. If this turns out to be wrong we could be reborn as a cockroach or find ourselves burning in hell for the rest of eternity. And that ought to be a cause for concern, since the duration of this life is rather insignificant compared to that of eternity!
The pre-Socratic philosophers were trying to reduce the stuff of the world to something simple and ideally unitary. Thus Thales thought it was made of water, Anaximenes that it was air and Heraclitus fire. Others, such as Democritus, even anticipated the idea of atoms, believing that matter consisted of indivisible particles that were too small for us to see. But, as can be seen from the Heraclitus quotation above, they were not exactly materialists in the sense of someone like Hobbes. The latter would have us believe that there is only matter and that we ourselves are entirely mechanical. The former were searching for some unifying principle that we could equally well call God.