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The Pre-Socratics. were 6 Th and 5 Th century BCE Greek thinkers. Early civilizations Began in the Levant region of southwest Asia. The emergence of civilization is associated with Agricultural Revolution occurred in various locations between 8,000 and 5,000 BCE. Philosophy Timeline.
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The Pre-Socratics were 6Th and 5Th century BCE Greek thinkers
Early civilizations Began in the Levant region of southwest Asia. The emergence of civilization is associated with Agricultural Revolutionoccurred in various locations between 8,000 and 5,000 BCE.
Philosophy Timeline Birth of Christ 8000 BCE 5000 BCE Present 1945-50 600 BCE 600 CE 1500 CE Civilization begins (?) Modern Philosophy Begins Post-Modern Philosophy Ancient Philosophy Philosophy Begins Modern Philosophy Medieval Philosophy
*Why were “pre-Socratics”? • Socrates is such an important figure in Western philosophy that we divide ancient philosophy into classical and pre-Socratic philosophers. • Socrates lived c. 469 BC – 399 BC • Presocratics introduced a new way of thinking about the world: • They went beyond Greek mythology.
Thales of Miletus (624-546 B.C.E) • A witty maid-servant saw Thales tumbling into a well and said that he • was so eager to know what was going on in heaven that he could not see • what was before his feet. • 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. • Main doctrine: He asserted water to be the principle of all things: • Landmass ends at water’s edge; so, earth is floating on water.
Thales was poor, so people believed the study of philosophy was useless. So through his skill in astronomy, Thalesperceived that there would be a large harvest of olives that year. Then, while it was still winter, and having obtained a little money, he put deposits on all the olive oil businesses that were in Miletus and Chios. He obtained them at a low price. When the season came for making oil, many people wanted the rights, and he sold them all at once for whatever terms he pleased; raising a large sum of money, he convinced everyone that it was easy for philosophers to be rich if they chose it, but that was not what they aimed at. [Aristotle, Politics, 1.11]
Thales’s Doctrine Thalessaid the principle is water (for which reason he declared that the earth rests on water). Perhaps he got this notion from seeing that the nutrition of all things is moist, and that heat itself is generated from the moist and kept alive by it (and that from which they come to be is a principle of all things). Perhaps he also got his notion from the fact that the seeds of all things have a moist nature, and that water is the origin of the nature of moist things. [Aristotle, Politics, 1.11]
First, Thales thought that reality is composed of only one thing, with all different things that we experience being nothing but various forms of water. • The task of metaphysics is to identify the primary substance and to equate it with reality.
Second, since what we perceive through the senses is not one thing, but many, Thales thought that reality could be known by reasoning about it. • By approaching it through intellectual knowledge, not sense knowledge.
Consequently, Third, Thales had in mind the distinction between appearances and reality. The common sense world, known through the senses, appears to be very different from the real world, known through the mind. • What is real is different from what appears to my senses to be real.
Thales introduced this new philosophical way of thinking about the world, a way that replaced mythological thinking.
Anaximander (c. 610 – c. 546 BC) • Student of Thales. • Invented the sundial, he also made clocks. • First to draw a map of the earth. • Earth cannot float on water. Where does water float on? • He argued that the force of opposites held it there. • The principle and primary element of all things was the Unlimited or boundless • the Unlimited is not itself a particular kind of thing, like water.
Anaximander is the first of the Greeks to write his ideas “The boundless is the original material of existing things; further, the source from which existing things derive their existence is also that to which they return at their destruction, according to necessity.”
[According to Anaximander,] there is a body distinct from the elements, the boundless, which is not air or water, in order that the other things may not be destroyed by their infinity. The elements are in opposition to each other: air is cold, water moist, and fire hot. Therefore, if any one of them were infinite, the rest would have ceased to be by this time. Thus, he said that what is infinite is something other than the elements, and from it the elements arise. [Aristotle, Physics, 3.3]
There are two basic ideas of Anaximander that are especially important for us: One is his identification of the basic stuff of reality with the “Unlimited”. • One thing is clear: the Unlimited is not a particular element, such as water. Any particular kind of thing is limited to being a thing of that kind.
For Anaximander everything originates from and dissolves into the Unlimited. • Every change involves a conflict of opposites. • He held a primitive theory of evolution to account for how the many kinds of things that now exist evolved from the unlimited. • Anaximander’s mysterious concept of the “Unlimited” uncannily resembles our contemporary notion of “energy”.
Furthermore, Anaximander argued that the earth does not rest on a vast ocean of water, as Thales held, and as many believed to be true at that time. • Instead, he believed that it hangs suspended at the center of the universe by the force of opposites.
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) • Wrote books on Education, on Politics, and on Natural Philosophy. • 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. • 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. • The nature of reality is constituted by numbers/proportions/mathematical relations.
Two types of mathematical ratios were especially important for Pythagoras: the Tetractysand musical harmony. The Tetractys is a mystical symbol involving ten points arranged in four rows: one, two, three, and four points in each row respectively: * ** *** **** The four rows represent earth, air, fire and water, and various combinations of the points generate important numbers and ratios.
The tetractys is a certain number, which being composed of the four first numbers produces the most perfect number, ten. For one and two and three and four come to ten. This number is the first tetractys, and is called the source of ever flowing nature. This is because, according to them, the entire cosmos is organized according to harmony, and harmony is a system of three intervals: the fourth, the fifth, and the octave. The proportions of these three intervals are found in the aforementioned four numbers. [SextusEmpiricus, Against the Mathematicians, 7.94-95]
Pythagoras declared that the soul is immortal, then that it changes into other kinds of animals. In addition, the things that happen recur at certain intervals, and nothing is absolutely new. Also, all things that come to be alive must be thought akin. Pythagoras seems to have been the first to introduce these opinions into Greece. [Porphyry, Life of Pythagoras, 19]
Pythagoras writes: “The soul is established in the body through number; which is to say, through immortal and incorporeal harmony.” • The soul is harmony of the body; thus the study of the harmonies of music and mathematics are a way to nourish the soul, to rid it of its impurities, of its “disharmonies”. • Mathematics and music are the keys to unlocking the secrets of reality. For Pythagorians, reality is number. • Pythagoras states that: “Number is the ruling and self-creating bond which maintains the everlasting stability of the things that compose the universe.”
The relationships between musical notes, harmony, may be expressed numerically. • For Pythagoras the universe has an order to it that, like the human soul, was a type of harmony, a harmony that could be expressed mathematically. • In addition, numbers can name groups of objects, and arithmetic equations can express quantitative relationships between these groups. • Pythagoras also had knowledge of geometry and knew that numbers can stand for things insofar as they express their shape, their size, their volume and some of their other dimensions, such a mass and location.
Mathematical systems, then, reflected a deeper pattern of nature, its order and structure—its harmony. • Today the world of natureas studied by physics is described primarily in mathematical terms. • The world is a mathematical place from its smallest particles to its largest quantities. • Plato learned much from Pythagoras.
To say that everything is number represents thinking at a very high level of abstraction. • Thales, Anaximander, and Anaximenes thought that nature was Unlimited stuff or water or air. • Pythagoras, however, did not identify reality with material stuff, but rather with properties and relationships. • Mathematical properties are possessed by all things, and mathematical relationships hold among them. • This was an advance in thinking, a theory not too far from modern science.
Mathematics builds its systems by accepting some statements as true (axioms) and deriving the truth of other statements from them (theorems). • These rules are essentially those of deductive logic. • Pythagoras was the first philosopher and mathematician ]to employ such rules, though it was left to Aristotle to develop them more fully.
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. • Everything flows on like a river—everything is a flux. • "You can't step into the same river twice”. • Identified reality with fire. “There is exchange of all things for fire and of fire for all things…” • 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.” • “Everything flows and nothing abides; everything gives new way and nothing stays fixed.”
For Heraclitus there is nothing permanent. “You cannot step into the same river, for other waters and yet others go ever flowing on.” • In another curious passage 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, as there is of wares for gold and gold for wares.” • He didn’t believe that what underlies all appearances is fire, as others have claimed it to be water or air. • Fire is a metaphor to indicate the transient nature of the universe.
For Heraclitus, there is no enduring substance of which all else is a variation. • All is becoming and nothing is fixed. • If this is true, then it seems deny the search for the ultimate substance (This seems to be the way that Aristotle interprets him). • Also this denies that any concept is objective. • But what in nature, if anything, plays the role of a permanent reality for Heraclitus?
Underlying continuous changing is an order at work. “This universe, which is the same for all, has not been made by any god or man…kindling itself by regular measures and going out by regular measures.” • So Heraclitus sees the universe as eternal: pay attention to “is the same for all” phrase and the “regular measures” phrase. • Heraclitus has a notion of the order with which things pass from one form to another. He says that: “Fire lives in the death of earth, air in the death of fire, water in the death of air, and earth in the death of water.” This conveys the general idea that there is an underlying order to change.
At the deepest core of reality is a creative process, a synthesis of opposing elements, where “cool things become warm, the warm grows cool; the moist dries, the parched becomes moist.” • This process gives rise to change—fire from earth, air from fire, water from air and earth from water. • Heraclitus calls this pattern the Logos, the rational order of the cosmos.
Logos is not apparent to the senses but must be discovered by the mind. • As Heraclitus expresses it: “Although this Logos is eternally valid, yet men are unable to understand it—not only before hearing it, but even after they have heard it for the first time. That is to say, although all things come to pass in accordance with this Logos, men seem to be quite without any experience of it...”
Parmenides of Elea (510-440 BCE) • Nothing changes, everything is permanent, everything is 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.
Parmenides said nothing changes, that everything is permanent, that everything is what he called Being. • How could he hold such a view in the face of so much apparent change, change that is so evident to our senses? • Things change their location (motion), or change from one sort of thing to another (wood becomes heat and ashes when burned), or change a property (a banana changes color from green to yellow).
The only surviving work of Parmenides is his poem, On Nature. The first part of the poem, called “The Journey”, talks about Parmenides being guided to the Goddess, who informs him that to be wise he must learn the “Way of Truth” and about false philosophical doctrines, “The Way of Opinion”, because to be wise he must learn “how to judge the mere seeming.”
Parmenides drew the distinction between appearances (“mere seeming”) and reality more sharply than any of the Presocratics who preceded him. • On the one hand, there are the senses that deliver to us our perceptions of the world, perceptions that produce mere opinion. • On the other hand, we have our mindsthat deliver reality to us. It is through reason and reason alone, that the Way of Truth is to be traveled by Parmenides. • With the senses we only travel only the Way of Opinion, the road of illusion and falsehood. • For Parmenides, Being is One. There are no “many” different sorts of things, no multiplicity. All is One and One is all.
After admonishing Parmenides to “Let reason be your judge” the Goddess tells him: “I will tell you of the two roads of inquiry which offer themselves to the mind. The one way, that It Is and cannot not-be, is the way of credibility based on truth. The other way, that It Is Not and that not-being must be, cannot be grasped by the mind; for you cannot know not-being and cannot express it.”
Let’s begin with the last sentence. The Goddess says “that not-being must be, cannot be grasped by the mind.” It cannot be known or expressed. ‘Known’ means ‘thought’, so the first point is that not-being cannot be thought or said. In a later passage of the poem, the Goddess confirms this by saying . . . “it is impossible to say or think that not-being is.”
The second point is that Being, “cannot not-be”. • But it seems, after all, that things that do exist could cease to exist. People are born, live, and die—to become not-being. • For Parmenides Being is anything that can be thought and spoken of. • He believes that anything that can be thought exists. In a later passage the Goddess says, “Thinking and the object of thought are the same,” In another place she says, “Thought and Being are the same.”
If what is real, Being, is what can be thought, and if not-being cannot be thought, then reality is only Being. There is no not-being. • What about a married couple that considers having a child, who currently is not. This child’s birth is an example of becoming, a category of existence that requires us to think of beings that both are and are not, that have not-being. • But this category is ruled out by Parmenides, because he believes that if you can think of something, then it exists—remember, “thought and being are the same.” • If it cannot be thought of, on the other hand, it does not exist. Things either are (Being) or are not (Nothing). There is no category for becoming.
So, there are only two categories, Being and not-being. • Things that exist and things that do not. • Of these two there is only one category of reality—Being, which is anything that can be thought about. • Not-being, which cannot be thought about, simply is not and should not be mentioned, since it is merely an illusion of the senses. • The Goddess says, “. . . men have established the habit of naming two thought-forms; therein they have erred, because one of the forms ought not to be named.”
From these two intuitions: (1) Being is, and (2) not-being is not, Parmenides deduces the following conclusions. • First: Being is eternal. It was not created nor can it be destroyed. It simply is. • It has no beginningbecause if it did, Being would have to come from not-being. But not-being is unthinkable and so it is nothing, and thus cannot produce anything. • So Being had no origin. Everything that Is did not “become” what it is, for then it would have had to not-be before it was. • There is no becoming, since becoming would require passing from not-being, or nothing, to Being, which is not possible. So Being just Is, eternally.
Second: Being is indestructible. It cannot cease to be because, again, it would have to pass from Being to not-being. Since not-being is nothing, and since something cannot become nothing then, passing away is just as impossible as coming to be. • I know you’re thinking, that coming to be and passing away are real. An apple is eaten and changes to human flesh; a river flows by with new water; a man dies and returns to the earth. • None of this really happens, says Parmenides; it appears to the senses that it does. • Change is a mere illusion. It is what the senses tell us about the world.
Third:Parmenides claims that Being is indivisible. It cannot be divided into parts that can be named. • There are no separate kinds of things. • If it had parts it would have divisions, and divisions are not-being, or nothing. • Divisions are the “holes” between beings and thus, as not-being, do not exist.
“[The One] is not divisible, since it is all alike, and there is no more of it in one place than in another, to hinder it from holding together, nor less of it, but everything is full of what is. For this reason it is wholly continuous; for what is, is in contact with what is.”
Fourth:since it is not divisible, Being is One. It has no parts. It is “one, continuous” it remains “always the same” and “stays fixed where it is”. • Moreover, The One is unmoving, since movement requires us to say that it is now in this position, but not in that position.
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.”
The paradox of the stadium runner: Imagine that a runner sets off on a race track. Before he can reach the finish line, he must pass the halfway point. Before he can do that, though, he must pass the 1/4-way point, and before that the 1/8-way point, and so on to infinity. The runner would have to cross an infinite number of way points in a finite time, and thus can never reach his goal.
The paradox of the motion of the arrow: (1) Anything occupying a place just its own size is at rest. (2) In the present, a moving arrow occupies a place just its own size. (3) Hence, in the present, a moving arrow is at rest. (4) However, in the present a moving arrow always moves. (5) Hence, a moving arrow is always at rest throughout its movement. The paradox here is that there’s good reason to say both that, first, the moving arrow is always at rest, and (b) the moving arrow is always in motion.