The pre-Socratic philosophers are recognized as the ones that laid the groundwork for all of western philosophy. It is safe to say that most of the work done by the pre-Socratic philosophers changed the way that we look at the ourselves and the world around us. The great thing about these philosophers is that they came up with explanations that tried to explain everything around them. Whether it was what we call physics, psychology, epistemology, etc... it was all one. One theory explained everything. Unfortunately, this tradition has not stood the test of time. In fact, today, philosophy and the study of nature (physics) are treated as distinct fields. To the pre-Socratics they were one and the same. What makes the pre-Socratics so interesting is the way that some of their many ideas are still valid today. Perhaps, the most striking example of this fact is the work done by the early Atomists, Democritus and Leucippus.

All of modern chemistry and physics are based on the same principles brought about by these Atomists. This essay will show that most of the Atomic Theory as proposed by Democritus and Leucippus, is still preserved today by modern science in one form or another. After all, modern things are just advancements of things before.

First, it should be noted that Leucippus was a teacher to Democritus in a town called Abdera off of the Aegean Sea around 400 B.C. (Gaarder 43). Thus Leucippus probably came up with the idea of atoms, and Democritus furthered the ideas. It is also important to know what the Atomic Theory was intended to prove. What the Atomic Theory tried to show was how change was possible, a question posed by the Eleatics. See, Democritus didn't believe in change. He couldn't agree that the transformations he observed every day in nature were due to change. However, it's obvious that that things do transform in nature. This is where the true genius of the Atomic Theory unfolds. Democritus postulated that at a very basic level, things don't change. The "things" that don't change are what Democritus called "atoms", meaning "uncuttable". He proposed that many of these atoms exist (infinitely many), and that they are extremely small. In fact they are "invisible because of the minuteness of their size" (McKirahan 308). It's the coming together and separation of these groups of atoms that result in change, as we observe in nature. That last sentence is the basic principle that all of modern science is based upon.

Democritus postulated that the atoms, along with being small, are indestructible and eternal. Thus, these atoms have always been and will always be. After all, nothing comes form nothing. All of this is very consistent with modern theories about energy. The Conservation of Energy, which is a fundamental physical law, relies on the indestructibleness of fundamental particles. What about the "big bang"? Did these particles exist before the existence of the universe? Well, according to Einstein ('s theory of relating mass with energy), this energy did exist, although it originated from one single point (according to "big bang" theories). This one point must have had all of the energy that we have today. All of the energy today is the same as the beginning of time. Thus, these atoms are eternal.

According to Democritus, the only way in which the atoms can be distinguishable between one another is in shape and size. The atoms of different shapes and sizes (infinitely many) come together (never touching, as then two atoms would be one) to form a new "compound". Thus, there are infinitely many compounds that can exist. This precise coming together of shapes is similar to the "Lock and Key Model" used to explain the the specificness of enzymes in the human body. Although, there are 111 known elements, people don't dismiss the possibility that there are still more elements to be "discovered". In fact, Democritus was correct in saying that everything is just mixtures of these elements.

The indestructibleness of the atom has been proven wrong with the existence of the sub-atomic particles: protons, neutrons and electrons. In fact, these sub-atomic particles are thought to be broken down into sub-sub-atomic particles such as quarks. Quarks have different colours, shapes and flavours (Okun 3). But then, a modern hypothesis is one of the existence of "Super-Strings" which takes into account space-time, gravity and spin (all the constituents of modern physics!) (Brink & Henneaux 7). It is thought that these strings are the fundamental unit. No doubt, in time people will posit the existence of smaller items. Does this prove Democritus incorrect? No, as Democritus never envisioned our modern view of the atom. Democritus believed that there existed a basic particle that existed. Democritus' atom could very well be a super-string. Since, most scientists believe that a basic substance must exist (whether electrons, quarks etc...), Democritus' view of an indestructible atom is conserved. It is the comparison of our atom and Democritus' atoms that causes the problem.

Another astounding concept devised by the early Atomists was the concept of The Void. According to Democritus, the void was "no-thing" (McKirahan 315). It is a concept different form air and space. In fact, the void is infinite in extension, and occupies space. "Where there is void there are no atoms, and where there are atoms there is no void" (McKirahan 315). It seems that this void can't exist, and according to Parmedian arguments, one can not speak of what doesn't exist. Democritus felt this argument coming, so he claimed "there is no more reason for the thing to be than the nothing" (McKirahan 314). Thus, when he speaks of nothing, this nothing does exist. The function of this void allowed for the atoms to move around and make interactions (however, not physically touching). This allowed for change to occur at a macroscopic level. Also, the void allowed for the separation of atoms, which in fact assured the distinctiveness of the different atoms. If there was no space between the atoms, one large atom would exist. The obvious modern equivalent of the void is of course the vacuum. A perfect vacuum exists where there are no particles in a space. In a vacuum, sound doesn't exist (to be discussed later), gravity and the velocity of light exist as perfect constants. Incidentally, the discovery caused an uproar in the church as God exists everywhere. However, a vacuum was absolutely nothing. Does God exist in a vacuum, which is nothing? Thus, does God exist nowhere? Theoretical physics are considered under perfect conditions. A vacuum is this perfect condition, as there is no air resistance thus, friction is neglected and hence, more accurate results can be attained. As shown, the concept of the void is a very viable idea that still exists today, although it's just called a perfect vacuum.

The concept of atomic motion is tackled by Leucippus, who claims that "no thing happens at random but all things as a result of a reason and by necessity" (McKirahan 321). The word "necessity" here is referring to the fact that since the atoms and the void exist, resulting in motion of atoms (like vibrations, according to Leucippus), things could not occur any other way. This necessity need not be the same as purpose. Thus, every motion and interaction of atoms can be explained. Hence, all atoms would remain motionless unless acted upon by another atom. Imagine watching a game of billiards. The 8-ball doesn't move unless it is first touched by another ball. This is what causes motion of atoms to exist. Sort of like, one big eternal billiard game where the balls keep hitting one another. What can be derived from this, is that an atom wants to be at rest. The atoms only move when forced to. An Englishman named Newton would exploit this idea about two thousand years later when formulating his famous three laws of motion. Newton's first law states that every body continues in its state of rest or in uniform velocity unless it is acted upon by a force (Ross 35). Newton's next two laws follow from the first law. Newton's Universal Law of Gravitation, is perhaps the greatest insight into nature ever. The law explains everything from intergalactic motion to nuclear particles, and everything in between. All of Newton's Laws together form the basis of what we today call Classical Mechanics, the study of motion. Newton is known as the father of modern physics. If this is true, the early Atomists are clearly the grand-fathers.

The way in which the Atomists viewed the universe is somewhat similar to our contemporary theory. It should first be noted that to the Atomists, the idea of universe and KOSMOS are different from one another. The universe is the sum of all atoms and of all the void. The KOSMOS is "a world system that is limited both spatially and temporally" (McKirahan 325). Thus, according to them the universe was infinite. This differs from the contemporary view of a finite universe. The modern view results from the Conservation of Energy. If the universe was infinite there would exist infinite energy, and thus an infinite supply of energy would exist. However, this is not the case. Energy can not be created nor destroyed, it can only take on many forms (potential, gravitational, kinetic etc...). Leucippus posited that the universe is composed of an infinite amount of KOSMOI. These KOSMOI are made up of atoms, and can be destroyed back into the component atoms. He claims that a huge amount of KOSMOI would come together to form a "vortex". The atoms then begin to move apart and come together according to shape and size. The vortex then begins to rotate, and the small atoms move towards the peripheral, while the larger atoms move towards the centre. This is how our earth was created. "...as these (KOSMOI) whirl around by virtue of the resistance of the centre" (325) they form solid bodies. This is just like the physical concept of rotational motion. According to Centripetal Acceleration, when a body is rotating, an acceleration (thus a force) points always towards the centre. This results in heavy bodies moving towards the centre. Leucippus claimed that these KOSMOI came together to form all of the stars. This is bold as it attests that our KOSMOS is just like any other star. Our earth is nothing special. In fact, the thought of a geocentric universe is not possible according to Leucippus. There is no centre of the universe. Of course, this idea is held by modern scientists. However, since the modern view is of a finite universe, the centre of the universe must exist somewhere. The ramifications of this to the church once again were shocking, as one person could theoretically, be the centre of the universe. The worshipping of a "regular person", and not a traditional God wouldn't be wrong. Perhaps, anyone could be God!?!

The idea of a soul is not new to the Atomists. However, they claimed that the soul is composed of spherical soul atoms. Thus, to them the soul was a tangible object. The soul atoms were located everywhere in the body. When someone died the soul atoms didn't die (this would violate their fundamental ideas), rather the soul atoms left the body gradually to rejoin the earth and the universe. Unfortunately, modern physics has little to say about the soul. Robert Pirsig claims that the soul is one with quality. In fact, the greatest part of the soul is to realize that we are part of the universe, and that the soul must become one with the universe (Pirsig 261). It is thought that the Atomists didn't believe in the Pythagorean view of reincarnation, but clearly the components of a person's soul will live for eternity in one form or another in the universe.

Democritus and Leucippus also claimed that the sensations felt by senses are just atoms striking a sense organ. In fact, sound is just the movement of sound atoms hitting our ears. This is precisely the modern theory of sound. Sound is propagated by the wave-like motion of molecules in the air (Smith & Cooper 208). Take away the molecules (air) and sound can't exist, which is exactly what occurs in a vacuum. The atomists of concept of light and vision are a bit hard to understand. Granted, the true nature of light is still a mystery to physics, where light acts like a particle sometimes (Einstein postulated that light would be affected by gravity, just like a particle (Einstein 84)), and like a wave at other times (Pedrotti 3).

As shown, the ancient Atomic theory as postulated by Leucippus and Democritus has been the starting point of all modern science. It is fascinating that they thought that the same concepts could be applied to all things despite size. Some paintings from more recent times (the past three hundred years) show an old man with one hand pointed to the heavens and the other pointed towards the ground. This echoes the sentiment that holds today: As above, so below. The archaic and modern Atomic Theory are somewhat related in concepts. However, it has been only recently that empirical evidence has shown that the existence of atoms is very plausible. Any astute physics student will tell you that for any phenomenon, there are infinitely many explanations for that specific phenomenon. Until all hypotheses are tested, Democritus and Leucippus will stand correct.