Natural Philosophy

Natural philosophy is the orderly investigation of the phenomena of the universe through the use of experimental observation and/or logical reasoning. It was introduced by Alexander the Great in his creation of the Library of Alexandria. This gave consent to the pursuit of knowledge and, since Alexander was taught by a natural philosopher, to the study of natural philosophy. In Ancient Greece (480-323 BCE), natural philosophers observed particular things like the phenomena of the natural world, along with abstract things like the nature of reality. These natural philosophers looked for universal principles by which phenomena could be explained; which among these philosophers included Heraclitus, Parmenides, and Plato. The philosopher Heraclitus (ca. 545-475 BCE) of Ephesus believed that flux, or change, was the basic principle of the universe. Parmenides (ca. 515-440 BCE), Heraclitus’ successor, believed that Being is rational and that only what can be thought can exist. Since “nothing” cannot be thought of without thinking of it as something, there is no nothing, there is only Being. Plato (427-347 BCE), who was one of the most powerful thinkers in history, emphasized the immortal and unchallengeable consciousness over the mortal and changeful body. But Plato advanced a new division, favouring the invisible world of Forms or Ideas in opposition to the physical world. Evidently, Heraclitus, Parmenides, and Plato used the basic principle of change to explain the nature of the universe.

As interpreted by the later Greek philosophical tradition, Heraclitus stands primarily for the radical thesis that everything is in flux. Born in 545 BCE in Ephesus, a city on the coast of modern Turkey, he was a man of strong and independent philosophical spirit. Unlike the Milesian philosophers, whose subject was the material beginning of the world, Heraclitus focused instead on the internal rhythm of nature, which moves and regulates things, namely, the Logos (Rule). Heraclitus is the philosopher of the eternal change. He expresses the notion of eternal change in terms of the continuous flow of the river, which always renews itself. Although it is likely that he took this thesis to be true, universal flux is too simple a phrase to identify his philosophy. Heraclitus accepted only one material source of natural substances: fire. He held that fire is the primal element out of which everything else arises. Fire is the origin of all matter; through i,t things come into being and pass away. The fire itself is the symbol of perpetual change because it transforms a substance into another substance without being a substance itself. “There is something about the nature of fire that gives insight into both the appearance of stability and the fact of change”(Palmer 24). From this vision, he obtained some remarkable conclusions. Change occurs within a range of opposites. The unity of opposites means that opposites cannot exist without each other – there is no day without night, no summer without winter, no warm without cold, no good without bad. Comparing the union of opposites with the contrary tension of a bow and a lyre is perfectly in harmony with his theory of flux and fire. Also, he focused on aspects such as Logos, which ruled change in an orderly manner. This cosmic order made change a rational phenomenon rather than the chaotic, random one it appeared to be. The basic principle of change to explain the universe is evident throughout Heraclitus’ beliefs.

Another philosopher, Parmenides, believed that being is rational and that only what can be thought of can exist. Since “nothing” cannot be thought of without thinking of it as something, there is no nothing; there is only Being. A Greek philosopher from Elea in southern Italy and founder of the Eleatic school, Parmenides was the most influential of the Presocratic philosophers. He is the first philosopher to insist on a distinction between the world of appearances and reality. Parmenides held that the multiplicity of existing things, their changing forms and motion, are but an appearance of a single eternal reality, “Being”, thus giving rise to the Parmenidean principle that “all is one.” From this concept of Being, he went on to say that all claims of change or of non-being are illogical. Given this, it follows that Being is uncreated, indestructible, eternal, and indivisible. Furthermore, Being is spherical because only a sphere is equally real in all directions. “Being has no holes because, if Being is, there can’t be any place where Being is not” (Palmer 28). From this argument, it follows that motion is impossible because motion would involve Being going from where Being is to where Being isn’t, but there can’t be such a place as the place where Being isn’t. In fact, for Parmenides the very idea of empty space was an impossible idea. Either space is a thing, in which case it is something and not nothing, or it is nothing, in which case it does not exist. Because all thought must have an object and because nothing is not an object, the idea of nothing is a self-contradictory idea. Evidently, Parmenides understood that Being is rational, and only what can be thought exists.

One of the most powerful thinkers in history, Plato, emphasized spiritual values and made ideas, rather than matter, the basis of everything that exists. He supported the invisible world of the Forms, or Ideas, in opposition to the physical world. Plato was born in 427 BCE in Athens to an Aristocratic family. He received the finest education Athens had to offer from Sophocles. Plato “argued for the existence of an ideal world” (Donley). Plato recognized two worlds: the world of Forms or Ideas, which is the ideal world, and the world of Particulars, which is the world we see. He saw the particular world and the things in it, as imperfect copies of the world of Forms or Ideas. These forms are unchangeable and perfect and are only comprehensible by the use of the intellect or understanding, whereas the particular world is constantly changing. But indeed, in the particular world, the particular objects we see around us bear only a dim resemblance to the more ultimately real forms of Plato’s world of Forms. Since he reasoned that what we learn about physical objects empirically by means of the senses, we look at them, taste them, listen to them, and so on, he thought that sense experience is not a valid means. None of the information we gain in this way is reliable or trustworthy; therefore, we don’t have real knowledge of the visible world, just mere opinion. Whereas we learn about the Forms not by means of the sense but by means of reason. We don’t need to look at the forms or listen to them; indeed, we cannot do so; we can figure out what they are by thinking about them. In a sense, knowledge of the forms also enables us to understand the visible world better. When we understand the Forms, we know what the visible world is a pale imitation of. Plato also understood that our physical bodies are a part of the in world of the particular world. Our sense organs, by means of which we learn about the visible world, are also part of our physical body. But our souls are part of the world of Forms, which, for Plato, is more or less identical to our reason. So one result of coming to learn about the Forms is that we will become less concerned with physical matters and less reliant on our unreliable senses for knowledge. It is obvious that Plato heightened the idea of the world of Forms and the particular world.

Conclusion 

Heraclitus, a natural philosopher, argued that everything is in flux. Parmenides, Heraclitus’ successor, understood that Being is rational and that only what can be thought can exist. Since “nothing” cannot be thought of without thinking of it as something, there is nothing; there is only Being. Plato recognized our universe as two worlds: the world of Forms or Ideas, which is the ideal world, and the world of Particulars, which is the world we see it as. These natural philosophers sought universal principles by which phenomena could be explained, which, among these philosophers, included Heraclitus, Parmenides, and Plato.

Bibliography:

Works Cited

Donley, Jeffery. Plato. Valencia Community College. Orlando. 05 Nov. 2003.

Palmer, Donald. Looking at Philosophy: The Unbearable Heaviness of Philosophy Made

Lighter. 3rd ed. New York: McGraw-Hill, 2001.

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