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ANCIENT PHILOSOPHY THALES, HERACLITUS, PARMENIDES LECTURE PROFESSOR JULIE YOO Significance of the Presocratics From Religious Anthropomorphic Explanation to Scientific and Philosophical Explanation Caveat About the Label, “Presocratic” Naturalism Use of Observation Ancient Western Chemistry and Physics Milesians – Thales Heraclitus Parmenides Type v Token Monism Argument for (Token) Monism Linguistic Support for Parmenides’s Denials The Void Motion Change Coming into Being and Going out of Being Plurality Lecture on the Presocratics: Thales, Heraclitus, and Parmenides Page 1 of 10 SIGNIFICANCE OF THE PRESOCRATICS From Religious Anthropomorphic Explanation to Scientific and Philosophical Explanation From roughly 600 BC to 400 BC, Western civilization underwent a novel way of thinking about the world and human beings. Prior to the emergence of the Pre-Socratics, thinkers mainly followed the religious tradition of their day to explain why things happen. There is a clear example of this style of explanation in the story of the four seasons and the Greek gods: the earth undergoes death and decay in fall and winter because Demeter, the goddess of agriculture, mourns the passage of her daughter, Persephone, to the underworld of Hades, but then the earth witnesses growth and abundance in spring and summer, because Persephone returns to her mother from Hades, making her mother happy. We now know that we have the four seasons because of the elliptical shape of the orbit of earth around the sun; when the earth is father away, the weather gets colder, and so on. The Presocratics didn’t know astronomy well enough to know this about the weather, but this style of explanation is exactly what they were looking for, and it is the kind of explanations they attempted to give that set the foundation for modern science and philosophy. While nowadays, the disciplines are all separated into different fields and departments – biology, physics, geology, political science, philosophy – this division would be been baffling to the Presocratics, as well as Plato, Aristotle, and the Hellenistic philosophers. This is because the study of nature, all of nature, was all a part of doing philosophy. Thus, the term, “philosophy,” used to be a broad umbrella term that included all these disciplines that now go by different labels. Caveat about the Label, “Presocratic” The label makes it seem as if the people who fall under it all lived before Socrates, but this is not true. Some of them were not only contemporaries of Socrates, but were born even after the birth of Socrates. The reason this label is used is to distinguish Socrates from these other philosophers in his outstanding focus upon ethics – the human good and the good way to live. The Presocratic philosophers were less interested in issues of human conduct than in issues of how the world worked. Naturalism The Presocratics are recognized for their commitment to explain the world in terms of its inherent principles, rather than outside, humanly, characterized forces (the gods, with their human motivations and character traits). A good example of this is Xenophanes’s explanation of a rainbow as a colored cloud, which is a remarkably for its accuracy and its daring challenge to the prevailing explanation that rainbows are sign from the gods sent by the messenger god Iris. For the Presocratics, nature is a complete and self-ordering system whose operation can be understood by observation and reason. It is not a chaotic jumble of events that occur according to the whims of the gods. Lecture on the Presocratics: Thales, Heraclitus, and Parmenides Page 2 of 10 Use of Observation and Critical Reasoning Another important feature of this newfound way of explaining the world is the use of observation to support one’s argument. This is certainly not the case when one explains things in religious or poetic terms. In religion and poetry (story-telling), one uses either imagination or just hearsay, like the testimony of a priest, to back up one’s explanation. There is a clear break from this way of justifying when one uses one’s own careful observations of the natural world. We can compare the following means of justification: Religious/Poetic: There is a rainbow because the gods want to send us humans a message, and we can believe this because this is what the priest said. Philosophical/Scientific: There is a rainbow because there is a colored cloud descended from the sky, and we can believe this because it is observable by everyone. Even when direct observation was not available, the Presocratics were very concerned about coming up with good reasons that could support their view. We will see non-observational theory construction with the work of Parmenides, where the emphasis relies primarily upon Reason, as opposed to Sense Perception (observation). Ancient Western Chemistry and Physics Whereas the list of basic elements – fire, earth, air, and water – seems very primitive and child-like, its purpose was as sophisticated as our modern periodic table. We use the table to explain properties of light bulbs, plant nutrition, cars, buildings, etc., like their stability, durability, strength, and so on. And the explanations we get of these properties of objects in terms of the properties of their more basic compounds are quite complex and sophisticated. The Ancient Greeks had the same intentions when it came to explaining the things in the world that they experienced. MILESIANS – THALES The earliest thinker who is credited as a Pre-Socratic Philosopher is Thales of Miletus. There are two others from Miletus who followed in the intellectual footsteps of Thales, Anaxaminder and Anaximedes, who also developed philosophical views that are of interest in their own right. However, we will focus on Thales since he is regarded as the very first philosopher. Lecture on the Presocratics: Thales, Heraclitus, and Parmenides Page 3 of 10 According to Aristotle’s reconstruction of Thales’s philosophy (Metaphysics 1.3 983b 18 – 27), Thales came to the conclusion that everything was ultimately made up of water on the basis of the following: 1. 2. 3. 4. Fact: “[T]he nourishment of all things is moist …” Fact: “[T]he hot itself comes to be from this and lives on this ...” Fact: “[T]he seeds of all things have a moist nature…” The best explanation for the above facts is that water is the principle of all nature (everything is water). 5. Water is the principle of all nature. In different fragments, Thales also says that the earth rests on water. The conclusion does not state this. In fact, as Aristotle points out, it is ambiguous between two separate ideas: A. Water is the original source of everything; everything comes from water. B. Water is the basic constituent of everything; everything is water in form or another. For our purposes, what is notable about the argument is its attempt to explain how the natural world operates by focusing on an alleged feature internal to the world, not on a story about how some gods got together to create seeds, animals, etc. and its use of observation to support each of the premises. HERACLITUS Heraclitus calls logos the single principle of all nature that guides and controls nature or the physical world. Logos, which is often translated as “account,” or “explanation,” or “word,” are inadequate, but the idea is that logos can capture the objective truth about the world. Moreover, unlike some skeptical stances about the intelligibility of the world, Heraclitus holds that logos is capable of being comprehended. It is within the grasp of human reason and observation, which is revealed only to those who do the hard work of philosophizing rigorously. According to Heraclitus, contemplation about the divine law reveals that the world is a collection of many opposites and that things are always from one side of the opposite to the other – youth and old age, life and death, hot and cold, and so on. This is his Doctrine of the Unity of Opposites, and it functions as a reason for adopting his radical claim that change is the ultimate nature of the world. 1. Fact: Everything in the world is a collection of opposites. 2. The best explanation for this fact is that the world is always Becoming, which means that it is in a constant state of change or flux. 3. The world is in a constant state of change or flux. The passages about never being able to step into the same river twice famously illustrate this idea. One might think that Heraclitus would agree with Thales and favor water as the basic principle of all nature, but Heraclitus claimed that it was fire that physically signified the logos of the world. This is because fire has the feature of constantly changing (its shape) and yet remaining the same as itself – fire. Another important difference from Thales is that Heraclitus Lecture on the Presocratics: Thales, Heraclitus, and Parmenides Page 4 of 10 treated fire only as a physical sign of the ultimate nature of the world, not as the fundamental principle of the world. For Thales, water is the fundamental principle of the world. PARMENIDES Heraclitus and Parmenides are usually discussed together because they hold opposing views about the nature of the world. For Heraclitus, the world consists of opposites and continuous change. For Parmenides, the world is single, undifferentiated, unchanging unity. Parmenides presented his views in verse. In the “Proem” (a preface) to his poem, Parmenides describes a journey he takes with a goddess who makes a promise to reveal to him the ultimate truth about the world. But rather than just taking her word for it, the goddess urges Parmenides to test and assess her arguments in his own. This is most philosophical! After the Proem is a section called “Truth,” and after follows a section called “Doxa” (beliefs or opinions). In “Truth,” Parmenides presents the view for which is most famous. According to this view, the world is ultimately unchanging. It is a single, unchanging, undifferentiated, timeless Being, contrary to Heraclitus’s view that it is always in a state of Becoming. Parmenides’s view is known as monism. His argument for monism is based on a priori considerations (knowledge generated by reason alone), unlike Heraclitus’s argument, which is based on a posteriori considerations (knowledge generated by observation and experience). Type v Token Monism The monism of Parmenides is radical. It is radical in that it is not merely an affirmation of the existence of only one kind of thing, but the affirmation of the existence of one single thing. We can appreciate this difference by drawing the distinction between types and tokens. Here is an example: a car is a type in that there can be many tokens of that type in the form of your car, my car, your friend’s car, and so on. Redness is also another type, where the many tokens of it can be found on fire trucks, stop signs, T-shirts, etc.. For any general term you can come up with – rectangularity, smoothness, shininess, etc. – we have a type that can have many tokens in the form of objects that possess those types. With this distinction, we can see how it is one thing to say that there is only one kind of thing or type of thing – that everything is water – where you allow that there can be many instances or tokens of that one type of thing – this body of water, that body of water, and so on, and quite another thing to say that there can only be one token of one kind of thing and that there is nothing more to the world than this one single thing. It is this latter, radical, thing that Parmenides is claiming about the world. Whereas Thales was a type monist, since he allowed for there to more than one object that are all made of water, Parmenides is a token monist, since he allows for there to be only one object, period. The Paremenidean Being is a single type that has only a single token, and there is nothing else that exists in the world. For this reason, he is a token monist. Lecture on the Presocratics: Thales, Heraclitus, and Parmenides Page 5 of 10 Lecture on the Presocratics: Thales, Heraclitus, and Parmenides Page 6 of 10 Parmenides’s Argument for Token Monism The argument is best understood in two parts – one about the world as a single unitary Being, and the other about the non-existence of change. Part 1 1. We have knowledge of the world. 2. If we have knowledge of the world, then the world must be a single Being. 3. The world must be a single Being. This part of the argument establishes Parmenides’s monism. The argument is deductively valid (via modus ponens). Premise 1, for Parmenides, is not in dispute. What needs support is Premise 2. Part 2 The support for Premise 2 relies on two principles, one about the connection between knowledge and existence, and the other about the sufficiency of what is (is not) the case to what must be (cannot be) the case. Principle of Knowledge and Existence: There can be knowledge of x if and only if x exists. Principle of Change and Nonexistence: If x changes (a green banana changes into a yellow one) the past form of x no longer exists. These two principles are crucial for supporting the claim that there can be no change. By the Principle of Change, if there is change, then there is something that does not exist (how x used to be). By the Principle of Knowledge and Existence, we cannot know that which does not exist. This gives us the following argument. 1. If we have knowledge of the world, then the world cannot change. 2. If the world cannot change, then the world is a single Being. 3. If we have knowledge of the world, then the world is a single Being. The impossibility of knowing that which does not exist, for Parmenides, not only rules out change, but a lot of things such as coming into being and passing out of being, plurality and difference, and void. Let us list these things that Parmenides denies: a. b. c. d. e. There is no Void or Emptiness (Nothingness) There is no Movement or Motion There is no Change or Alteration There is no Generation or Destruction (Coming into Being and Going out of Being) There is no Plurality or Difference Lecture on the Presocratics: Thales, Heraclitus, and Parmenides Page 7 of 10 Linguistic Support for Parmenides’s Denials1 One way of understanding this strategy is by following this linguistic principle of reference: “x” is a meaningful term if and only if it refers to something that exists. Thus, “the moon,” “California,” “oranges,” and so on are meaningful terms because they refer to things that exist. Terms like “dragons,” “Tinkerbell,” “the current queen of the US,” are not meaningful because there is nothing that these terms pick out. For Parmenides, the following sentence does not have genuine meaning: “Santa Clause comes from the North Pole.” This is because “Santa Clause” does not pick out an existing individual. On this model of linguistic meaning, statements about the void or movement or change, etc., are all statements about things that do not exist. Consequently, they are not meaningful, and are therefore not about real things in nature. The Void and Nothingness Take, for instance, a statement about the void. “There is a void.” → “There is nothingness.” → “Nothingness exists.” The final claim that nothingness exists, however, is paradoxical on this model of reference, because in order for the sentence to have meaning, nothingness must being something, not nothing, in order for the term “nothing” to refer. But that is precisely what is being denied. Motion or Movement The denial of a void makes it difficult to account for motion. In order for one thing to move to another place, the place to which it moves must be empty and thus full of void. But the above argument doesn’t allow for void. Thus, there can be no motion. Another argument for the same conclusion is that in order for an object x to move from A to B, we have to say that x is not at A when it is at B (and vice versa). But then we have talk about what does not exist. For any motion to occur, we have to say: “x is not at A.” But this ties us up in a paradox, because a sentence cannot express meaning unless it refers to a situation that actually obtains. But the above statement is denying exactly this. 1 This is known as the “problem of negative existentials,” and it did not receive rigorous logical treatment until the 20th C in the work of Bertrand Russell. A lecture on Russell’s treatment of negative existentials is on the moodle site under “Resources.” Lecture on the Presocratics: Thales, Heraclitus, and Parmenides Page 8 of 10 Coming into and Going Out of Being/Generation and Destruction As with motion, statements that track growth or decay have to express a paradoxical negative. For instance, if at a certain time x did not exist (like you in the year 1952), but then came into existence at a later time, then you have to say: “In 1952, x does not exist.” Contrary to the sentence, x most certainly has to exist in 1952 order for the “x” in the sentence to meaningfully a fact about x. But that is what the sentence denies. Due to this paradox, the whole phenomenon coming into Being or passing out of Being – growth and decay – are considered illusory. Change There is a variety of changes: there is growth and diminution, which involves the accretion or loss of parts, there is replacement, which involves the exchange of some of a thing’s old parts with new parts, and there is change where a thing has a feature F at one time a loses that feature at a later time. Take the case of a ripening banana, which is where a thing has a feature at one time, which it loses only to gain another at a later time. On Tuesday an unripe banana is green, but then by Thursday, it loses it’s green hue and becomes yellow. As with growth and decay, as well as motion, that requires you to express a paradoxical negative: “On Tuesday, the banana was green.” This makes reference to the past. But the past is gone! It does not exist. Therefore, we cannot meaningfully make a true statement about the past because all true statements must be only about situations that obtain. This leads to the general denial of the passage of time. There is no difference between past, present, and future. The one Being is in a timeless state to which these tenses to not apply. Plurality As far as appearances go, there is a plurality of things, not just one big undifferentiated thing. There is your book, my pen, your neighbor’s car, etc. And each of these things have many different properties: your book has a certain shape, a certain size, a certain weight, etc. Many different things apply to your book. It appears that there is a plurality of individual things as well as a plurality of different features that belong to a single thing. Parmenides’s denial of plurality in favor of monism is a denial of both the existence of many individual things and different features of a thing or several things. His argument for this is the most difficult to decipher from his writings. But there are several ways building on Parmenides’s denial of the other things to support his denial of plurality. 1. If the world is not one Being, but more than one Being, then we have at least two Beings B1 and B2. But if these things are separate from each other, then there has to Lecture on the Presocratics: Thales, Heraclitus, and Parmenides Page 9 of 10 be a space in between them, and this space would have to be empty. However, it was demonstrated before that there can be no void anywhere. 2. If we have at least two Beings, B1 and B2, then we have to say of B1 that it is not B2 (and vice versa). More specifically, we have to deny the existence of B1’s being B2 (or vice versa), which is a statement about what does not exist. But these statements are paradoxical. 3. If a thing has several features, F1 (shape) and F2 (weight), then just as before, we have to we have to say of F1 that it is not F2 (and vice versa). More specifically, we have to deny the existence of F1’s being F2 (or vice versa), which is a statement about what does not exist. Arguments (2) and (3) respectively rule out the plurality of things and the plurality of features. On Parmenides’s view we have one giant cosmic Being which is a pure unity that does not change, has no parts or pluralities or qualities, not past, present, or future, and is indestructible. Lecture on the Presocratics: Thales, Heraclitus, and Parmenides Page 10 of 10