The Pre-Socratics

Early civilizations Began in the Levant region of southwest Asia. Other regions around the world soon followed. The emergence of civilization is associated with Agricultural Revolution, which occurred in various locations between 8,000 and 5,000 BCE. This revolution marked the beginning of stable agriculture and animal domestication, which enabled economies and cities to develop increasingly large population, division of labor, specialization, development of writing…and philosophy!

8000 BCE

Civilization begins (?)

5000 BCE

Philosophy Begins

Birth of Christ

600 BCE

600 CE

Ancient Philosophy

Medieval Philosophy

Modern Philosophy Begins

Modern Philosophy

Post-Modern Philosophy

1500 CE

1945-50

Present 2012

Philosophy Timeline

The pre-Socratics were 6Th and 5Th century BCE Greek thinkers

Thales of Miletus (624-546 B.C.E) First Western Philosopher

Anaximander of Miletus (610-546 B.C.E)Anaximenes of Miletus (585-528 B.C.E)Pythagoras (582-496 B.C.E)Xenophanes (570-470 B.C.E) Leucippus (c550 B.C.E)Heraclitus (535-475 B.C.E)Parmenides of Elea (510-440 B.C.E)Anaxagoras (500-428 B.C.E)Zeno of Elea (490-430 B.C.E)Empedocles (490-430 B.C.E) Democritus (460-370 B.C.E)Protagoras (481-420 B.C.E) Diogenes (412-323 B.C.E)

*Why were they called “pre-Socratics”?

Socrates is such an important figure in Western philosophy that we divide ancient philosophy into classical philosophers and pre-Socratic philosophers.Socrates lived c. 469 BC – 399 BC

Pre-Socratic Introduced a new way of thinking about the world:

At that time Greek myths explained the origins of the universeand of man: personifications of Earth and Sky mating and produced land, mountains, and seas.

Mythology explained the nature of the world by making up fantastic stories.

The early Greek, Pre-Socratic philosophers attempted to explain the world around them in more natural terms than those who relied on mythological explanations.

Thales of Miletus (624-546 B.C.E)

First philosopher in the West first who studied astronomy. Foretold the eclipses and motions of the sun in 585. Divided the year into 365 days. Measured pyramids by watching their shadows: Wait till your shadow is equal to your height and apply *Pythagorean theorem*.Main doctrine: He asserted water to be the principle of all things: at low temperature, water becomes rock, at very high temperature air. Water is essential for life of all organisms. Physical things take the form of either solid, or liquid, or gas. Since water can assume all these forms it is possible that everything is a form of water.landmass ends at water’s edge; so, earth is floating on water.

Continues

…Thales

Of course he was wrong. Today we know that NOT everything is water. What is important to learn from Thales’ statement has more to do with the kinds of questions: If “everything is water” was his answer, then the question must have been something like this: What is the one, fundamental thing of which all other things are composed? This question tells us several things about what he must have believed:

he realized that there must be one fundamental element that makes up all matter, just like science today.

since what we perceive through the senses is not one thing, he must have realized that mere observation cannot afford us knowledge of the world. He must have realized that to understand nature it is necessary to think outside the box: observation + reasoning. This marked a leap forward from mythology, which merely made up stories.

Anaximander (c. 610 – c. 546 BC)

student of Thalesinvented the sundial, he also made clocks.Earth cannot float on water. Where does water float on? What supports that water that supports the earth? So, he believed the earth is unsupported, hanging in space. had no theory of gravity to explain what holds the earth, but he argued that the force of opposites held it there.The principle and primary element of all things was the Unlimited or boundless, no exact definition. Single formless substance that can take various forms.Undefined substance.the Unlimited is not itself a particular kind of thing, like water.Anaximander’s odd concept of the “Unlimited” actually is not too far from our contemporary view that “energy” is the ultimate stuff.

Anaximenes (b. 585 BCE, d. 528 BCE)

Student of Anaximander dismissed the theory of Anaximander: earth must be supported by something—by air.said that the principle of everything was the air, “As our souls, being air, hold us together, so breath and air embrace the entire universe.”disagrees with Thales that water is the ultimate basis of reality; Does not agree with Anaximander that the source of all things can be some vague, poetic entity such as the Unlimited.Air is all around us. It is necessary for life to breathe it. It fills the sky, and upon it floats the earth.He said the three elements, earth, fire and water, arose from the air: condensation and rarefaction. Pure air is the most rarefied substance, but it can condense into heavier and heavier forms. according to degree of condensation—fire, wind, clouds, water, and earth are formed.

Pythagoras (582-496 BCE)

Pythagoras wrote books on Education, on Politics, and on Natural Philosophy. carried geometry to perfection, when he discovered that the square of the hypotenuse of a right-angled triangle is equal to the squares of the sides containing the right angle.Introduced the idea of “square” and “cube” of a number, applying geometrical concepts to arithmetic. that the soul is something different from life and is immortal. that the soul of man is divided into three parts: intuition, reason , and mind. Enormously Influenced Plato.The nature of reality is constituted by numbers/proportions.

Xenophanes (570-470 BCE)

He wrote philosophical poems and disputed the things Hesiod and Homer said about the Gods.His doctrine was, that there were four elements of existing things. He thought that the clouds were produced by the vapor that was borne upwards from the sun. That God was in no respect resembling man:

But if (horses) or cows or lions had handsTo draw and produce works of art as men do,Horses would draw the figures of gods like horsesAnd cows like cows, and they would make their bodies

Just as the form which they each havethemselves. Ethiopians say that their gods are snub-nosed and black, and Thracians that theirs have blue eyes and red hair.

Sicilian philosopher pupil of Pythagoras. It is said that he once went up to mount Etna and leaped into its crater to prove he was a god. that there were four elements, FIRE, WATER, EARTH, and AIR. And that it is friendship by which they are united, and discord by which they are separated. that the sun is a vast assemblage of fire, and that it is larger than the moon. that the soul inhabits every kind of form of animals and plants.

Empedocles (490-430 BCE)

Leucippus (c550 BCE)Democritus (460-370 BCE)

his principal doctrines were, that all things were infinite, and were interchanged with one another.that the universe was a vacuum, and full of bodies; also that the worlds were produced by bodies falling into the vacuum.that the nature of the stars originated in motion.he was the first philosopher who spoke of atoms as principles.

Here is how Aristotle, who had much to say about Democritus, described his theory: “According to the theory of Democritus it is the nature of the eternal objects to be tiny substances infinite in number. Accordingly, he postulates also a place for them that is infinite in magnitude, which he designates by these names—the void, the nothing and the infinite; whereas he speaks of each individual atom as the yes-thing, the dense, and being. He conceives them as so small as to elude our senses, but as having all sorts of forms, shapes, and different sizes. Treating these as elements, he conceives of them as combining to produce visible and otherwise perceptible objects.”

…ATOMISM

That atoms and the vacuum were the beginning of the universe.Nothing was created out of nothing, and that nothing was destroyed so as to become nothing. “1St law of thermodynamics: Energy can be neither created nor destroyed.” That the atoms produced all the combinations that exist; fire, water, air, and earth. For Democritus, the material objects evident to our senses were all composed of atoms. They were eternal, uncreated entities. They could never be destroyed, only recombined in a different manner. In such a mechanistic world, where everything happens in machine-like fashion, there is no room for the exercise of free will. This view is called determinism. Determinism is the belief that every event has a cause. Free choices are thought of as choices that are not rigidly caused, as choices that could have been different. In a mechanistic world, however, everything that happens is determined by previous causes to happen in precisely the way that it does, and in no other way. My choices are not free because, like everything else, they are brought about by the prior movements of atoms, movements which were themselves

Heraclitus (535-475 BCE)

everything is constantly changing; nothing is permanent. Everything is a coming together of opposites: the path up to the mountain and the path down are the same path; the young you and the old you are the same you; if I say my glass is half empty and you say it’s half full we agree with each other.that everything flows on like a river—everything is a flux.That "You can't step into the same river twice”.Nothing is permanent. Everything changes constantly. Things as well as men are never the same for two moments…he appears to identify reality with one of the four elements, fire. “There is exchange of all things for fire and of fire for all things…”Universe is made of fire. Fire seems a thing/object, but in reality is a process in perpetual motion.Change is the law of life, and there is nothing definite in the universe. “This universe, which is the same for all, has not been made by any god or man, but it always has been, is, and will be—an ever-living fire, kindling itself by regular measures and going out by regular measures.”

Parmenides of Elea (510-440 BCE)

If Heraclitus said that all was change, though change according to regular patterns, Parmenides said nothing changes, that everything is permanent, that everything is what he called Being. If what is real, Being, is what can be thought or said, and if not-being cannot be thought or said, then reality is only Being. There is no not-being. Being is eternal. It was not created nor can it be destroyed.Everything that Is did not “become” what it is, for then it would have had to not-be before it was. Nothing comes out of nothing: everything must always have existed.Being is One Reality must be/universe must be one single unchanging entity.When we experience change is because it occurs within an unchanging system.It is a fixed and frozen unity, always has been, and always will be that way.

Anaxagoras (500-428 BCE)

that the sun was a mass of burning iron, greater than Peloponnesus, and that the moon contained houses, and also hills and ravinesThe winds he thought were caused by the rarification of the atmosphere, which was produced by the sun. Thunder, he said, was produced by the collision of the clouds; and lightning by the rubbing together of the clouds.Earthquakes were produced by the return of the air into the earth. All animals he considered were originally generated out of moisture, and heat, and earthy particles: and subsequently from one another. (EVOLUTION)It is said that he was persecuted for impiety because he said that the sun was a fiery ball of iron.

Zeno of Elea (490-430 BCE)

Zeno's paradoxes are a set of philosophical problems to support his teacher’s, Parmenides, doctrine that "all is one" and that, contrary to the evidence of our senses, the belief in plurality and change is mistaken.motion is illusory.

Achilles and the Tortoise:“ In a race, the quickest runner can never overtake the slowest, since the pursuer must first reach the point whence the pursued started, so that the slower must always hold a lead.”

Dialogue by Lewis Carroll:

The Tortoise challenged Achilles to a race, claiming that he would win as long as Achilles gave him a small head start. Achilles laughed at this, for of course he was a mighty warrior and swift of foot, whereas the Tortoise was heavy and slow. “How big a head start do you need?” he asked the Tortoise with a smile. “Ten meters,” the latter replied. Achilles laughed louder than ever. “You will surely lose, my friend, in that case,” he told the Tortoise, “but let us race, if you wish it.” “On the contrary,” said the Tortoise, “I will win, and I can prove it to you by a simple argument.” “Go on then,” Achilles replied, with less confidence than he felt before. He knew he was the superior athlete, but he also knew the Tortoise had the sharper wits, and he had lost many a bewildering argument with him before this. “Suppose,” began the Tortoise, “that you give me a 10-meter head start. Would you say that you could cover that 10 meters between us very quickly?” “Very quickly,” Achilles affirmed. “And in that time, how far should I have gone, do you think?” “Perhaps a meter – no more,” said Achilles after a moment's thought.

“Very well,” replied the Tortoise, “so now there is a meter between us. And you would catch up that distance very quickly?” “Very quickly indeed!” “And yet, in that time I shall have gone a little way farther, so that now you must catch that distance up, yes?” “Ye-es,” said Achilles slowly. “And while you are doing so, I shall have gone a little way farther, so that you must then catch up the new distance,” the Tortoise continued smoothly. Achilles said nothing. “And so you see, in each moment you must be catching up the distance between us, and yet I – at the same time – will be adding a new distance, however small, for you to catch up again.” “Indeed, it must be so,” said Achilles wearily. “And so you can never catch up,” the Tortoise concluded sympathetically. “You are right, as always,” said Achilles sadly – and conceded the race.

In other words...

Suppose I wish to cross this room. First, of course, I must cover half the distance. Then, I must cover half of the half. Then, I must cover half the remaining distance. Then I must cover half the remaining distance . . . and so on forever. The consequence is that I can never get to the other side of the room.

What this actually allegedly shows is to that all motion impossible, for before I can cover half the distance I must cover half of half the distance, and before I can do that I must cover half of half of half of the distance, and so on, so that in reality I can never move any distance at all, because doing so involves moving an infinite number of small intermediate distances first.

The arrow paradox

“ If everything when it occupies an equal space is at rest, and if that which is in locomotion is always occupying such a space at any moment, the flying arrow is therefore motionless.”

For motion to occur, an object must change the position which it occupies. For example, consider an arrow in flight. In any one instant of time, the arrow is neither moving to where it is, nor to where it is not. It cannot move to where it is not, because no time elapses for it to move there; it cannot move to where it is, because it is already there. In other words, at every instant of time there is no motion occurring. If everything is motionless at every instant, and time is entirely composed of instants, then motion is impossible.

Protagoras (481-420 BCE)

in every question there were two sides to the argument exactly opposite to one another: "Man is the measure of all things”“Concerning the Gods, I am not able to know to a certainty whether they exist or whether they do not. For there are many things which prevent one from knowing, especially the obscurity of the subject, and the shortness of the life of man.”he was banished by the Athenians. And his books were burnt in the market-place. Instituted contests of argument, and charged money to teach how to win arguments. (sophism).

Diogenes of Sinope "The Cynic" (c412-323 BCE)

He said that in reality everything was a combination of all things: that in bread there was meat, and in vegetables there was bread, and so there were some particles of all other bodies in everything, communicating by invisible passages and evaporating. Music and geometry, and astronomy, and all things of that kind, he neglected, as useless and unnecessary. maintained that all the artificial growths of society were incompatible with happiness and that morality implies a return to the simplicity of nature: "Humans have complicated every simple gift of the gods.“When he was asked where he came from, he replied, "I am a citizen of the world

In Conclusion

The Pre-Socratics have offered solutions to one of the many fundamental questions of life, What is the nature of reality? they questioned the ordinary concept of reality.their explanations of the world were free from reference to gods and spirits and other personal forces. The Pre-Socratics demythologized nature.They invented the concept of nature as an impersonal place, a concept that we all take for granted today.Realized that our senses often cannot afford us a true picture of reality and that there was a deeper reality to existence, different from the way that the world appeared to us in our daily lives.Introduced notions that were influential within both philosophy and later science. Particular theories, for example, were precursors to their later scientific cousins: theories of evolution, atomism were developed. The very idea of a natural law also arose from their speculations.…and then comes Socrates.