Who Were the Pre-Socratics and Why Were They Important? - "Philosophy: A Historical Survey" by James Fieser


Why are many of the Ancient Greek thinkers often held in such high esteem today? What was so special about their culture that we identify them as one of the origins of Western culture? Well, what's unique about the Greeks is that they were one of the first to identify a set of core questions that they wanted answered, and gave answers that broke with a mythical tradition for a more rational one. Before the philosophers, Homer's universe was controlled by the gods, gods who were often just as capricious as men. The universe was something controlled by the whims and wills of the gods of Olympus, with the only universal force being fate which seemed to act as something like an impersonal law. After Homer, the other great Greek writer Hesiod took a step forward in introducing a new view of the gods, one in which they were more bound by an impersonal moral force to the universe. Thus, it was a huge step towards the first Pre-Socratics positing a view of the universe that moved away from mythology and towards natural philosophy. 

The two fundamental questions that the Pre-Socratics concerned themselves with were; "What is the nature of things?" and "How do things change and yet still retain their basic identity?" 1 [They were trying to wrestle with the fact that in nature things change but also retain their identity through those changes.] What, then, is the cause of the change? What's the source of a thing's continuing identity? To solve these problems, some philosophers emphasized the reality of change, while others emphasized the reality of identity. [Aristotle will later innovate on them and come up with the idea that something can be in a state of the mixture of both change and identity at the same time, or in his words, "act and potency."]

It is also this basic question that is going to concern not only the Pre-Socratics, but will also be the inspiration for the philosophy of Socrates and Plato. In the Pre-Socratics one can also see the development of the idea of the "One" which is so prominent in Plato later on. In the Pre-Socratics it has the meaning of referring to the one unifying element or principle from which the things of the universe come. Also a common theme in the Pre-Socratics is an appeal to mythical causes when their materialist explanations of chance and randomness break down, so to speak. Aristotle will use this observation later on to show that one cannot side step the rational intelligence behind the universe. One last notable point is the Pythagorean tradition which identifies the universal nature of things with something intellectual, numbers, rather than something physical. This is also going to the impetus for the breakthrough of Socrates.]

Thales - All is Water

Thales lived between 624 and 546 BC in Miletus in Ancient Greece. He was an all around wise man and proto-scientist, using geometry to measure things from the pyramids, to the distance of ships at sea, to predicting an eclipse of the sun. 2 Thales was the first to ask the question regarding the nature of things. What are things made up of? We often observe different types of entities in nature, from tree to moon to dirt. Also sometimes things transform into different types of materials, while still maintaining some similarity to their past. How can this be the case? Thales thought that there was the "One" elements or "stuff" that made up everything and also was able to become all the different materials in nature. Thales believed this universal element to be water. Why would this be the case? Well, thinking about nature, it is water that makes things grow. Water also evaporates and freezes, showing that it can be in different states. More importantly than his speculation that water was the universal element that lay behind the changing nature of things, was just the fact that he brought up the question regarding the universal nature of things. A question which kicked off the Western philosophical tradition. 3

Anaximander - The Boundless

Anaximander was a disciple of Thales and represents a further step in philosophy in that he not only speculates about the primary stuff of the elements, but gets into speculation regarding the ultimate stuff of the universe altogether, bypassing mythological accounts for a more naturalistic one. Anaximander held that there were several types of elements, not just water. More importantly these elements were derived from something more fundamental which was infinite and eternal, the "boundless realm." 4

"The indeterminate boundless is the unoriginated and indestructible primary substance of things, yet it also has eternal motion. As a consequence of this motion, the various specific elements came into being as they 'separated off' from the original substance." 5 

The One, for Anaximander, was the "boundless," and from this there were many versions of the universe that existed being created and destroyed over time by the opposite cosmic forces that balance on another out. 6

Anaximenes - All is Air

A third philosopher from Miletus, Anaximenes, was a disciple of Anaximander. He lived from 585 - 528BC, and followed a middle way between his two predecessors. The boundless was too vague, he though, and water too concrete. Rather, Anaximenes posited "air" as the fundamental element from which all things are made. The different elements are made from the density of air. The more dense or less dense gave rise to qualitatively different elements. Expansion causes heat, for example, while contraction causes coolness and hard things. 7 Thales, Anaximander, and Anaximenes all lived on the coast of Asia Minor in Miletus, and thus are called Ionians (region of Ionia) or the Milesian philosophers. Now we are going to break from their tradition and spread out over Greece. 

Pythagoras - Numbers

Pythagoras was born on the island of Samos and lived from 570 - 497 BC. He eventually moved to southern Italy and where he had a group of students and followers around him. This group of thinkers was advanced in mathematics and came to philosophize that all things were not made up of elements, but of numbers. There was also a religious cult that surrounded Pythagoras similar to the other mystery religious cults of the time. 8 They had a goal of spiritual purification and to attain immortality for their souls. This was done by participation in theoretical thinking and reflection. For the mind to leave the changing nature of the lower things of this world and reflect on the unchanging world of numbers was a type of participation in the divine. 

An example of how numbers could be at the root of all things is that they discovered that musical notes and octaves could be expressed in mathematical ratios. There was a mathematical expression for reality itself. All things were numbers to them and represent spatial volume. 9 One is a point from which all others come. Two is the union of two points which form a line. Three points can be turned into geometrical plane and four points into a 3D object. The odd and even aspect to numbers also helped explain why opposites exist throughout all of nature in different ways. 10

"All things had numbers, and their odd and even values explained opposites in things, such as one and many, square and oblong, straight and curved, or rest and motion. Even light and dark are numerical opposites, as are male and female, and good and evil." 11

Here they also furthered the conceptual vocabulary of philosophy up to this point by introducing the idea of "form." Form was what imposed a limit on the nature of reality to make it what it is, to achieve the harmony that is needed for something to be itself. Whether its a harmony in medicine or in music, a limit or form is necessary. Pythagoras, as is seen later in the history of philosophy, was a huge influence on the great Plato. 12 

"The true number, or figure, therefore refers to the proper balance of all elements and functions of the body. Number, then, represents the application of limit (form) to the unlimited (matter), and the Pythagoreans referred to music and medicine only as vivid illustrations of their larger concept, namely, that all things are numbers." 13

Heraclitus - Fire and Flux 

Heraclitus lived from 540 - 480 BC and was from Ephesus. As one of the Pre-Socratics he furthered the development of thought at the time by emphasizing the nature of change that takes place all around us. So far, different thinkers have speculated about the nature of the common element in things that's the same, here Heraclitus shifts that focus some. He introduces the concept of "flux." The idea is that things are always different from one moment to the next, whether that's trying to step in the same river twice or the movements of the human soul. Even amidst the flux, though, there has to be an element of which stays the same through the change. So for Heraclitus there still must be a unity as well as the flux. 

Interestingly, Heraclitus thought that the elements posited previously were too static, so he fixed that element of unity as the element of fire. 14 Fire is unique in that it is a transformative process and element itself. In this way, the process or catalyst of change is also the element of unity in things. The process of flux in the universe centers around that which goes into the fire and is transformed like fuel, and that which comes out of the fire as its product. The world then never is destroyed but only changes its form through the process. 

But what is the nature of the fuel that goes into the fire and the products that come out? Well Heraclitus describes two ways in which fire is the source of those as well, the "upward" and "downward" paths. In the downward path fire is condensed into different elements like water and earth. In the upward path fire earth is transformed into water and that water into living things. In these transformations, again, nothing is lost, only transformed. 15 "With this description of the constant transformation of things in fire, Heraclitus thought he had explained the rudiments of the unity between the one basic stuff and the many diverse things in the world." 16 

Heraclitus, though, recognized that this process does not happen by random. Rather, the highest faculties of reason is the real cause for order and harmony through this process. He was a pantheist in that the One, or God, for Heraclitus is fire. It's in all things and also orders and transforms the universe. 17 Thus there is a rational or lawlike principle in all things. Fire in its highest form provides the ability to reason, like it. It is the spark of the divine and the natural law which all men have access to. 18 "This is particularly so concerning his conviction that there is a common universe available to all thoughtful people and that all people participate in God's universal Reason or universal law."  19 

Heraclitus also uses this idea of eternal strife to explain the balance of opposites in the universe. Opposite forces and experiences must be so, but end up balancing one another out in a beautiful harmony. 20 "In the One the many find their unity. Thus, in the One 'the way up and the way down is the same,' 'good and ill are one,' and 'it is the same thing in us that is quick and dead, awake and asleep, young and old.' This solution of the conflict of opposites rests upon Heraclitus's major assumption that nothing is ever lost, but merely changes its form. 21

Parmenides - Change is Illusion

Parmenides lived from 510 - BC in Southern Italy called Elea. There he formed a school of philosophy known as the Eleatics. Parmenides takes up the same question as the other Pre-Socratics, but takes quite a fresh view. He held that all change is an illusion. Rather, all that exists is unchanging, has no parts and cannot be destroyed. This is "the One," [and it is a perfect sphere.] All distinctions between things are illusions as well. 

How could someone hold a position like this, one might ask? Well, Parmenides asks us not to look with our senses but to look with our mind, with logic. Something that exists, exists. We cannot conceive of things that have no existence. 22 To say that something comes into existence or goes out of existence is to say that it was "not" in existence at one point. If someone was not in existence then it will never be in existence. Therefore, all that is, is ... and all that is not, is not. We must logically move past our senses and realize logically that change is an illusion therefore. All things are, or all things are not. Also, to say that there is a difference between things is to posit distinctions of non existence between them. Rather, all things exist and so the differences of things is an illusion as well. The same is true with motion or change within things. He talks about this distinction as being between "appearance" and "reality." 23

[While seemingly a strange philosophy, it is actually one of the most important ideas which sparked the great minds of Plato and Aristotle who both responded to this.]

Zeno - Four Paradoxes About the Material World

Zeno was one of the great disciples of Parmenides and was born around 489 BC in Elea. He took to defending the philosophy of Parmenides by showing that to hold the common view that change is real would lead to logical conclusions of clear absurdity. Like Parmenides, he holds that our senses deceive us and lead us to false conclusions which logic does not. Zeno, then came up with a set of famous paradoxes to make this point clear, that nothing changes and all is one. 

The first paradox is called the racecourse. Its goal is to show that motion/change is impossible. In the paradox a runner has a racecourse set out in front of him to run. The problem is that before the runner can get to the end, he must get to the halfway mark. But before he can get to the halfway mark, he must reach half way before that, and half way before that, and so on. The runner actually cannot proceed at all because there's an infinite number of points between every other two points. Motion then must be an illusion. 24 

The second paradox is called "Achilles and the Tortoise." In the story the great warrior Achilles gives a tortoise a head start in a race. In reality we assume that Achilles would catch the tortoise easily, but logically, if we listen to Zeno, that's not what happens. Since the tortoise has a head start, Achilles has to first reach where the tortoise was before he can think of passing him. But in the time it takes Achilles to reach where the tortoise was with his head start, the tortoise has already moved on further. So Achilles must try to catch the tortoise at his next spot, but the time in which it takes him to get to that spot, the tortoise has already moved to a third spot. So on and so forth such that Achilles keeps gaining on the tortoise but never catches him. Thus, motion must really be an illusion. 

The third paradox is that of the arrow. Imagine shooting an arrow towards a target. If one considers that each point along the way has some amount of space to each, a quantity, then the arrow has an infinite number of points to pass through, like the other paradoxes. If on the other hand, a point has no quantity or space, then the arrow would be at rest, and motion would also be impossible, because no space plus no space is still no space. Thus motion is an illusion and the arrow never reaches the target in reality. 

The fourth paradox has to do with the "relativity of motion" and goes something like this. You have three cars all parallel to one another. The top car doesn't move while the bottom to cars pass one another briefly so that all the cars line up together. From the perspective of the two moving cars who met in the middle of the stationary car, they only passed half of each other. Yet from the perspective of the moving cars to the stationary car they passed the whole of the stationary car in the same amount of time. Therefore, motion is a relative concept. 25

These paradoxes show the logical pitfalls of admitting that there can be change and divisibility in the material world. An absurd quality of physical matter is its potentially infinite divisibility, begging the question for what matter actually is. On the other hand, to take away its quantity is to deny it exists at all. Therefore, Parmenides and Zeno came to the conclusion that there is simply unchanging being, one, unified, and motionless. 26

Empedocles - A First Attempt at a Middle Way

Empedocles lived from 490 - 430 BC, also in Italy. He is the first to attempt at finding a middle way between the two extremes of change and stability of the other Pre-Socratics. He agreed with Parmenides that being is material, eternal, and indestructible, but could not accept that all that existed was the One. 27 In order to reconcile the reality of change, he said that being is not the One, but the Many. There are four fundamental elements that are themselves changeless and indestructible; air, earth, fire, and water. When these elements "intermingle" together they create all the other elements which generate and decay. 

But how do such precise and meaningful forms of things become generated by this intermingling? Empedocles appeals to a higher ordering cause, namely two fundamental forces of the universe, love and strife. Love attracts the elements together generating certain entities. Strife pulls them apart, decomposing them. This happens in a cycle which never stops in four major stages. When there is all love everything is drawn together. As strife enters the equation a little bit then some changes occur. As strife begins to take over then decomposition begins its process. Finally strife takes over completely and all the four elements are totally separated until love returns and unifies them all and the process starts over again. 28

Anaxagoras - Mind Orders Reality 

Anaxagoras lived from 500 - 428 BC on the coast of Asia minor. While Anaxagoras agreed with Empedocles' explanation for the most part, he thought that the forces of love and strife were too impersonal to accomplish such rational ordering that he saw in the universe. Instead he believed that a rational mind was at the cause of the order in things. This mind took all the elements, which were bunched together, and began to spin them. From this spinning they began to disperse and for into mixtures of different amounts, creating everything else in its ordered way. There are two fundamental groups of mixtures, the "warm, light, rare, and dry" and the "cold, dark, dense, and moist." 29 The dense stayed closer in to the vortex while the lighter got spun further out, creating the land and the sky. Hot, fiery, clumps also shot out into the aether which are the stars and sun. 

While matter is eternal on its own and is only ordered by mind, mind is all present in the universe as an animating principle, sustaining living things. 

"Still, what Anaxagoras had to say about reason was of great consequence in the history of philosophy because he thereby introduced an abstract principle into the nature of things. He differentiated Mind and matter. While he many not have described mind as completely immaterial, he nevertheless distinguished Mind from the matter it had to work with. He stated that Mind, unlike matter, 'is mixed with nothing, but is alone, itself by itself,' ... Thus, while matter is composite, Mind is simple." 30

[Here we see some foreshadowing of Aristotle's idea of the immaterial forms being in things.]

The Atomists - Particles, the Void, and Chance

Finally, there are two famous men who provided the "Atomist" theory, Leucippus and Democritus. Democritus lived from 460 to 360 BC. In response to Parmenides' denial that there could be such a thing as space or emptiness because by definition that would be non-being which can't be a thing, the Atomists redefined the idea of space, not a something like other material objects, but as something more akin to an empty container in which matter could interact. Within this container are tiny indivisible particles that are indestructible, eternal, and infinite. Having a few different kinds of particles, they can interact with one another to form the different types of being in the universe. 31

"...the atomists now said that there are an infinite number of atoms, each one being completely solid in itself. These atoms contain no empty spaces and therefore are completely hard and indivisible. They exist in space and differ from each other in shape and size, and because of their small size, they are invisible. Since these atoms are eternal, they did not have to be created. Nature consists, therefore, of two things only: space, which is a vacuum, and atoms. The atoms move about in space, and their motion leads them to form the objects we experience." 32

Notably, the atomists leave out the idea of design or mind from their theory. Rather, all is random and chance encounters between the atoms. There is also no account of the origin of motion in these atoms. [Something which Aristotle will be very critical of later on.] 33


1 - Fieser, James and Samuel Enoch Stumpf. Philosophy: A Historical Survey With Essential Readings, Tenth Edition. McGraw Hill (New York) 2020. Pg 4.

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