XMind

Philosophers

1. Ancient

   1. Pre-Socratic cir. 585-450 BCE

      1. Milesian

         1. Thales

            1. System

               There is, however, another set of traditions about Thales from which something may be learnt. They are not of a popular character, since they attribute to him certain definite scientific achievements. One of the most important of these, the prediction of a solar eclipse, is reported by Herodotus (i. 74). The existence at Miletos of a continuous school of cosmologists give credit to the preservation of such traditions. We are further told on the authority of Aristotle's disciple Eudomos, who wrote the first history of mathematics, that Thales introduced geometry into Hellas. However, the evidence is incomplete since no writings by Thales were extant even in the time of Aristotle, and it is believed that he wrote nothing. In the annals of Greek philosophy he was probably the first who looked for a physical origin of the world instead of resting upon mythology. As such he is credited with being the first human being who can rightly be called a man of science.

               1. thales.doc

         2. Anaximander

            1. System

               Anaximander thought it unnecessary to fix upon air, water, or fire as the original and primary form of body. He preferred to represent it simply as a boundless something from which all things arise and to which they all return again. He was struck by a fact which dominated all subsequent physical theory among the Greeks, namely, that the world presents us with a series of opposites, of which the most primary are hot and cold, wet and dry. If we look at things from this point of view, it is more natural to speak of the opposites as being 'separated out' from a mass which is as yet undifferentiated than it is to make any one of the opposites the primary substance. Anaximander argued that Thales made the wet too important at the expense of the dry. He said that things 'give satisfaction and reparation to one another for their injustice, as is appointed according to the ordering of time.' This conception of justice and injustice recurs more than once in Ionic natural philosophy, and always in the same connection. It refers to the encroachment of one opposite or 'element' upon another. The formation of the world is due to the 'separating out' of the opposites. Anaximander's view of the earth is a curious mixture of scientific intuition and primitive theory. On the one hand, the earth does not rest on anything, but swings free in space. The reason he gave was that there is nothing to make it fall in one direction rather than in another. He inferred this because his system was incompatible with the assumption of an absolute up and down. On the other hand, though, he gives the earth a shape intermediate between the disc of Thales and the sphere of the Pythagoreans. He regarded it as a short cylinder 'like the drum of a pillar'.

            2. Aperion

         3. Anaximenes

            1. System

               Anaximenes (d. 502 BCE.) Anaximenes was a Greek philosopher of Miletus, a younger contemporary and pupil of Anaximander, who died about 502. He was not a great original genius like Anaximander, and in some respects his cosmology falls far short of his predecessor's. His title to remembrance is based on his discovery of the formula which for the first time made the Milesian theory coherent: of rarefaction and condensation. He regarded 'air' -- the air we breathe, but also that which thickens into mist and water -- as the primary form of body; it holds an intermediate stage between water and fire. Thus, his theory resembles that of Thales. On the other hand, he thought of this air as boundless and as containing an infinite number of worlds, in this respect following Anaximander. The solitary fragment quoted form his work shows that he was influenced by the analogy of the microcosm and the macrocosm. 'As our soul,' he says, 'which is air, holds us together, so do breath and air encompass the whole world.' The world is thought of as breathing or inhaling air from the boundless mass outside it. This air he spoke of as a 'god'. It is maintained that the Milesian cosmology was based on the primitive and popular theory of 'the four elements'. However, the scientific conception of an 'element' did not exist at this date. We shall see later that this was due to Empedocles, and it is only the place that the old quaternion of Fire, Air, Earth, and Water occupied in his system (and afterwards in that of Aristotle) that has led to these being called 'the four elements'. It is an unfortunate confusion, but it is very difficult to avoid it, and we must continue to use the word 'element' in two senses which have very little to do with one another. The spirit of Ionian civilization had been thoroughly secular, and this was one of the causes that favored the rise of science. The Milesian school came to an end with the fall of Miletus in 494 BC, but 'The Philosophy of Anaximenes', as it was called, continued to be taught in other Ionian cities.

               1. anaximines.doc

      2. Pythagoreans

         1. Pythagoras

            1. System

               Aristotle tells us that the Pythagoreans represented the world as inhaling 'air' form the boundless mass outside it, and this 'air' is identified with 'the unlimited'. When, however, we come to the process by which things are developed out of the 'unlimited', we observe a great change. We hear nothing more of 'separating out' or even of rarefaction and condensation. Instead of that we have the theory that what gives form to the Unlimited is the Limit. That is the great contribution of Pythagoras to philosophy, and we must try to understand it. Now the function of the Limit is usually illustrated from the arts of music and medicine, and we have seen how important these two arts were for Pythagoreans, so it is natural to infer that the key to its meaning is to be found in them.It is stated that he was a disciple of Anaximander, his astronomy was the natural development of Anaximander's. Also, the way in which the Pythagorean geometry developed also bears witness to its descent from that of Miletos. The great problem at this date was the duplication of the square, a problem which gave rise to the theorem of the square on the hypotenuse, commonly known still as the Pythagorean proposition (Euclid, I. 47). If we were right in assuming that Thales worked with the old 3:4:5 triangle, the connection is obvious. Pythagoras argued that there are three kinds of men, just as there are three classes of strangers who come to the Olympic Games. The lowest consists of those who come to buy and sell, and next above them are those who come to compete. Best of all are those who simply come to look on. Men may be classified accordingly as lovers of wisdom, lovers of honor, and lovers of gain. That seems to imply the doctrine of the tripartite soul, which is also attributed to the early Pythagoreans on good authority, though it is common now to ascribe it to Plato. There are, however, clear references to it before his time, and it agrees much better with the general outlook of the Pythagoreans. The comparison of human life to a gathering like the Games was often repeated in later days. Pythagoras also taught the doctrine of Rebirth or transmigration, which we may have learned from the contemporary Orphics. Xenophanes made fun of him for pretending to recognize the voice of a departed friend in the howls of a beaten dog. Empedocles seems to be referring to him when he speaks of a man who could remember what happened ten or twenty generations before. It was on this that the doctrine of Recollection, which plays so great a part in Plato, was based. The things we perceive with the senses, Plato argues, remind us of things we knew when the soul was out of the body and could perceive reality directly. There is more difficulty about the cosmology of Pythagoras. Hardly any school ever professed such reverence for its founder's authority as the Pythagoreans. 'The Master said so' was their watchword. On the other hand, few schools have shown so much capacity for progress and for adapting themselves to new conditions. Pythagoras started from the cosmical system of Pythagoras (Internet Encyclopedia of Philosophy)

         2. Philolaus

         3. Alcmaeon

         4. Archytas

      3. Heraclitus

         1. System

            Heraclitus was a Presocratic Greek philosopher of Ephesus, who lived about BCE. 535-475. The date of Heraclitus is roughly fixed by his reference in the past tense to Hekataios, Pythagoras, and Xenophanes (fr. 16), and by the fact that Parmenides appears to allude to him in turn (fr. 6). This means that he wrote early in the fifth century BCE. He was an Ephesian noble, and had a sovereign contempt for the mass of mankind. He lived during the time of the first Persian domination over his native city. As one of the last of the family of Androclus, the descendant of Codrus, who had founded the colony of Ephesus, Heraclitus had certain honorary regal privileges, which he renounced in favor of his brother. He likewise declined an invitation of King Darius to visit his court. He was an adherent of the aristocracy, and when, after the defeat of the Persians, the democratic party came into power, he withdrew in ill-humor to a secluded estate in the country, and gave himself up entirely to his studies. In his later years he wrote a philosophical treatise, which he deposited in the temple of Artemis, making it a condition that it should not be published till after his death. He was buried in the marketplace of Ephesus, and for several centuries later the Ephesians continued to engrave his image on their coins. His great work "On Nature" (peri phuseos), in three books, was written in the Ionian dialect, and is the oldest monument of Greek prose. Considerable fragments of it have come down to us. The language is bold, harsh, and figurative; the style is so careless that the syntactical relations of the words are often hard to perceive; and the thoughts are profound. All this made Heraclitus so difficult a writer that he went in antiquity by the name "the Obscure" (skoteinos), and Lucretius attacks him on the ground (i. 638-644). From his gloomy view of life he is often called "the Weeping Philosopher," as Democritus is known as "the Laughing Philosopher." It is above all in dealing with Heraclitus that we are made to feel the importance of personality in shaping systems of philosophy. But it was not only the common run of men that Heraclitus despised; he had not even a good word for any of his predecessors. He agrees, of course, with Xenophanes in criticizing Homer, but Xenophanes himself falls under an equal condemnation. In a remarkable fragment (fr. 16) he mentions him along with Hesiod, Pythagoras, and Hekataois as an instance of the truth that much learning does not teach men to think. The researches of Pythagoras, by which we are to understand his harmonic and arithmetical discoveries, are rejected with special emphasis (fr. 17). Wisdom is not a knowledge of many things; it is the clear knowledge of one thing only, and this Heraclitus describes, in true prophetic style, as his Logos (word/fire), which is 'true evermore', though men cannot understand it even when it is told to them (fr. 2). Perfect knowledge is only given to the gods, but a progress in knowledge is possible to men. We must try, then, to discover, what Heraclitus meant by his Logos, the thing he felt he had been born to say, whether anyone would listen to him or not. As fire is the primary form of reality, the process of combustion is the key both to human life and to that of the world. It is a process that never rests; for a flame must always be fed by fresh exhalations as fuel, and it is always turning into vapor or smoke. The steadiness of the flame Heraclitus depends on the 'measures' of fuel kindled and the 'measures' of fire extinguished in smoke remaining constant. Now the world is 'an everliving fire' (fr. 20), and therefore there will be an unceasing process of eternal flux (panta pei). For Hereclitus, everything is in this process of flux, and nothing therefore, not even the world in its momentary form, nor the gods themselves, can escape final destruction. That will apply to the world at large (macrocosm) and also to the soul of humans (microcosm). Concerning the larger world, 'You cannot step twice into the same river' (fr. 41); concerning the human soul, it is just as true that 'we are and are not' at any given moment. As fire changes continually into water and then into earth, so earth changes back to water and water again to fire. The world, therefore, arose from fire, and in alternating periods is resolved again into fire, to form itself anew out of this element. The division of unified things into a multiplicity of opposing phenomena is "the way downwards," and is the consequence of a war and a strife. Harmony and peace lead back to unity by "the way upwards." Nature is constantly dividing and uniting herself, so that the multiplicity of opposites does not destroy the unity of the whole. A glance at the fragments will show that the thought of Heraclitus was dominated by the opposition of sleeping and waking, life and death, and that this seemed to him the key to the traditional Milesian problem of the opposites, hot and cold, wet and dry. He finds these opposites both at the level of the human soul and the larger cosmos. At the human level, the soul is only fully alive when it is awake, and that sleep is really a stage between life and death. If we look next at the macrocosm, we shall see the explanation is the same. Night and day, summer and winter, alternate in the same way as sleep and waking, life and death, and here too it is clear that the explanation is to be found in the successive advance of the wet and the dry, the cold and the hot. The existence of these opposites depends only on the difference of the motion on "the way upwards" from that on "the way downwards"; all things, therefore, are at once identical and not identical. The principle of the universe is "becoming," which implies that everything is and, at the same time, is not, so far as the same relation is concerned. 'The way up and the way down', which are 'one and the same' (fr. 69) are also the same for the microcosm and the macrocosm. Fire, water, earth is the way down, and earth, water, fire is the way up. And these two ways are forever being traversed in opposite directions at once, so that everything really consists of two parts, one part traveling up and the other traveling down. Paradoxically the everlasting fire of the world which creates its flux, also secures its stability. For the same 'measures' of fire are always being kindled and going out (fr. 20). It is impossible for fire to consume its nourishment without at the same time giving back what it has consumed already. It is a process of eternal 'exchange' like that of gold for wares and wares for gold (fr. 22); and 'the sun will not exceed his measures; if he does, the Erinyes, the auxiliaries of Justice, will find him out' (fr. 29). For all this strife is really justice (fr. 22), not injustice, as Anaximander had supposed, and 'War is the father of all things' (fr. 44). It is just this opposite tension that keeps things together, like that of the string in the bow and the lyre (fr. 45), and though it is a hidden attunement, it is better than any open one (fr. 47). For all his condemnations of Pythagoras, Heraclitus cannot get away from the tuned string. With all his originality, Heraclitus remains an Ionian. In a sense, Heraclitus substituted fire for the 'air' of Anaximenes, who in turn had substituted 'air' for the water of Thales. Also, Hereclitus' notion of flux is a development of that Anaximenes' notion of rarefaction and condensation. Although Hereclitus has a doctrine of the soul, his fire-soul is as little personal as the breath-soul of Anaximenes. Some fragments superficially appear to assert the immortality of the individual soul. But, when we examine them, we see they cannot bear this interpretation. Soul is only immortal in Heraclitus ]so far as it is part of the everliving fire which is the life of the world. Seeing that the soul of every man is in constant flux like his body, what meaning can immortality have? It is not only true that we cannot step twice into the same river, but also that we are not the same for two successive instants. That is just the side of his doctrine that struck contemporaries most forcibly, and Epicharmos already made fun of it by putting it as an argument into the mouth of a debtor who did not wish to pay. How could he be liable, seeing he is not the same man that contracted the debt?

            1. heraclitus.doc

      4. Eleatic School

         1. Parmenides

            1. System

               Parmenides was a Greek philosopher and poet, born of an illustrious family about BCE. 510, at Elea in Lower Italy, and is is the chief representative of the Eleatic philosophy. He was held in high esteem by his fellow-citizens for his excellent legislation, to which they ascribed the prosperity and wealth of the town. He was also admired for his exemplary life. A "Parmenidean life" was proverbial among the Greeks. He is commonly represented as a disciple of Xenophanes. Parmenides wrote after Heraclitus, and in conscious opposition to him, given the evident allusion to Hericlitus: "for whom it is and is not, the same and not the same, and all things travel in opposite directions" (fr. 6, 8). Little more is known of his biography than that he stopped at Athens on a journey in his sixty-fifth year, and there became acquainted with the youthful Socrates. That must have been in the middle of the fifth century BCE., or shortly after it. permanently in a doctrine like that of Parmenides. It deprives the world we know of all claim to existence, and reduces it to something which is hardly even an illusion. If we are to give an intelligible account of the world, we must certainly introduce motion again somehow. That can never be taken for granted any more, as it was by the early cosmologists; we must attempt to explain it if we are to escape from the conclusions of Parmenides.ordinary man's view of the world, but an elaborate system, which seems to be a natural development the Ionian cosmology on certain lines, and there is no other system but the Pythagorean that fulfils this requirement. To this it has been objected that Parmenides would not have taken the trouble to expound in detail a system he had altogether rejected, but that is to mistake the character of the apocalyptic convention. It is not Parmenides, but the goddess, that expounds the system, and it is for this reason that the beliefs described are said to be those of 'mortals'. Now a description of the ascent of the soul would be quite incomplete without a picture of the region from which it had escaped. The goddess must reveal the two ways at the parting of which Parmenides stands, and bid him choose the better. The rise of mathematics in the Pythagorean school had revealed for the first time the power of thought. To the mathematician of all men it is the same thing that can be thought and that can be, and this is the principle from which Parmenides starts. It is impossible to think what is not, and it is impossible for what cannot be thought to be. The great question, Is it or is it not? is therefore equivalent to the question, Can it be thought or not? In any case, the work thus has two divisions. The first discusses the truth, and the second the world of illusion -- that is, the world of the senses and the erroneous opinions of mankind founded upon them. In his opinion truth lies in the perception that existence is, and error in the idea that non-existence also can be. Nothing can have real existence but what is conceivable; therefore to be imagined and to be able to exist are the same thing, and there is no development. The essence of what is conceivable is incapable of development, imperishable, immutable, unbounded, and indivisible. What is various and mutable, all development, is a delusive phantom. Perception is thought directed to the pure essence of being; the phenomenal world is a delusion, and the opinions formed concerning it can only be improbable. Parmenides goes on to consider in the light of this principle the consequences of saying that anything is. In the first place, it cannot have come into being. If it had, it must have arisen from nothing or from something. It cannot have arisen from nothing; for there is no nothing. It cannot have arisen from something; for here is nothing else than what is. Nor can anything else besides itself come into being; for there can be no empty space in which it could do so. Is it or is it not? If it is, then it is now, all at once. In this way Parmenides refutes all accounts of the origin of the world. Ex nihilo nihil fit. Further, if it is, it simply is, and it cannot be more or less. There is, therefore, as much of it in one place as in another. (That makes rarefaction and condensation impossible.) it is continuous and indivisible; for there is nothing but itself which could prevent its parts being in contact with on another. It is therefore full, a continuous indivisible plenum. (That is directed against the Pythagorean theory of a discontinuous reality.) Further, it is immovable. If it moved, it must move into empty space, and empty space is nothing, and there is no nothing. Also it is finite and spherical; for it cannot be in one direction any more than in another, and the sphere is the only figure of which this can be said. What is is, therefore a finite, spherical, motionless, continuous plenum, and there is nothing beyond it. Coming into being and ceasing to be are mere 'names', and so is motion, and still more color and the like. They are not even thoughts; for a thought must be a thought of something that is, and none of these can be. Such is the conclusion to which the view of the real as a single body inevitably leads, and there is no escape from it. The 'matter' of our physical text-books is just the real of Parmenides; and, unless we can find room for something else than matter, we are shut up into his account of reality. No subsequent system could afford to ignore this, but of course it was impossible to acquiesce Parmenides (Internet Encyclopedia of Philosophy) There is reason to believe that the Way of Belief is an account of Pythagorean cosmology. In any case, it is surely impossible to regard it as anything else than a description of some error. The goddess says so in words that cannot be explained away. Further, this erroneous belief is not the Parmenides (Internet Encyclopedia of Philosophy) http://www.utm.edu/research/iep/p/parmenid.htm (1 of 3) [4/21/2000 8:56:30 AM]

               1. parmenides.doc

         2. Zeno of Elea

         3. Melissus of Samos

         4. Xenophanes

            1. System

               Whatever is, always has been from eternity, without deriving its existence from any prior principles. Nature, he believed, is one and without limit; that what is one is similar in all its parts, else it would be many; that the one infinite, eternal, and homogeneous universe is immutable and incapable of change. His position is often classified as pantheistic, although his use of the term 'god' simply follows the use characteristic of the early cosmologists generally. There is no evidence that Xenophanes regarded this 'god' with any religious feeling, and all we are told about him (or rather about it) is purely negative. He is quite unlike a man, and has no special organs of sense, but 'sees all over, thinks all over, hears all over' (fr. 24). Further, he does not go about from place to place (fr. 26), but does everything 'without toil (fr. 25). It is not safe to go beyond this; for Xenophanes himself tells us no more. It is pretty certain that if he had said anything more positive or more definitely religious in its bearing it would have been quoted by later writers.Founder of the Eleatic school of philosophy, Xenophanes was a native of Colophon, and born about 570 BCE. It is difficult to determine the dates of his life with any accuracy and the facts of his life are also obscure. Xenophanes early left his own country and took refuge in Sicily, where he supported himself by reciting, at the court of Hiero, elegiac and iambic verses, which he had written in criticism of the Theogony of Hesiod and Homer. From Sicily he passed over into Magna Graecia, where he took up the profession of philosophy, and became a celebrated teacher in the Pythagorean school. Give way to a greater freedom of thought than was usual among the disciples of Pythagoras, he introduced new opinions of his own opposing the doctrines of Epimenides, Thales, and Pythagoras. He held the Pythagorean chair of philosophy for about seventy years, and lived to the extreme age of 105. Xenophanes was an elegiac and satirical poet who approached the question of science from the standpoint of the reformer rather than of the scientific investigator. If we look at the very considerable remains of his poetry that have come down to us, we see that they are all in the satirist's and social reformer's vein. There is one dealing with the management of a feast, another which denounces the exaggerated importance attached to athletic victories, and several which attack the humanized gods of Homer. The problem is, therefore, to find, if we can, a single point of view from which all these fragments can be interpreted, although it may be that no such point of view exists. Like the religious reformers of the day, Xenophanes turned his back on the anthropomorphic polytheism of Homer and Hesiod. This revolt is based on a conviction that the tales of the poets are directly responsible for the moral corruption of the time. 'Homer and Hesiod have ascribed to the gods all things that are a shame and a disgrace among mortals, stealing and adulteries and deceiving of another' (fr. 11). And this he held was due to the representation of the gods in human form. Men make gods in their own image; those of the Ethiopians are black and snub-nosed, those of the Thracians have blue eyes and red hair (fr 16). If horses or oxen or lions had hands and could produce works of art, they too would represent the gods after their own fashion (fr. 15). All that must be swept away along with the tales of Titans and Giants, those 'figments of an earlier day' (fr. 1) if social life is to be reformed. Xenophanes found the weapons he required for his attack on polytheism in the science of the time. Here are traces of Anaximander's cosmology in the fragments, and Xenophanes may easily have been his disciple before he left Ionia. He seems to have taken the gods of mythology one by one and reduced them to meteorological phenomena, and especially to clouds. And he maintained there was only one god -- namely, the world. God is one incorporeal eternal being, and, like the universe, spherical in form; that he is of the same nature with the universe, comprehending all things within himself; is intelligent, and pervades all things, but bears no resemblance to human nature either in body or mind. He taught that if there had ever been a time when nothing existed, nothing could ever have existed. Xenophanes (Internet Encyclopedia of Philosophy) http://www.utm.edu/research/iep/x/x-phanes.htm (1 of 2) [4/21/2000 9:02:23 AM]

               1. xenophanes.doc

      5. Pluralists

         1. Empedocles

         2. Anaxagoras

      6. Atomists

         1. Leucippus

         2. Democritus

            Democritus followed in the tradition of Leucippus, who seems to have come from Miletus, and he carried on the scientific rationalist philosophy associated with that city. They were both strict determinists and thorough materialists, believing everything to be the result of natural laws, and they will have nothing to do with chance or randomness. Unlike Aristotle or Plato, the atomists attempted to explain the world without the presuppositions of purpose, prime mover, or final cause. For the atomists questions should be answered with a mechanistic explanation ("What earlier circumstances caused this event?"), while their opponents searched for teleological explanations ("What purpose did this event serve?"). The history of modern science has shown that mechanistic questions lead to scientific knowledge, while the teleological question does not. The atomists looked for mechanistic questions, and gave mechanistic answers. Their successors until the Renaissance became occupied with the teleological question, which ultimately hindered progress. [24] Atomic hypothesis The hypothesis of Leucippus and Democritus held everything to be composed of atoms, which are physically, but not geometrically, indivisible; that between atoms lies empty space; that atoms are indestructible; have always been, and always will be, in motion; that there are an infinite number of atoms, and kinds of atoms, which differ in shape, size, and temperature. Of the weight of atoms, Democritus said "The more any indivisible exceeds, the heavier it is." But their exact position on weight of atoms is disputed.[25] Aristotle criticized the atomists for not providing an account for the cause of the original motion of atoms, but in this they have been vindicated as more scientific than their critics. Even if a prime mover or creator is supposed, that force remains unaccounted for. The theory of the atomists is, in fact, more nearly that of modern science than any other theory of antiquity. However, their theories were not wholly empirical, and their belief was devoid of any solid foundation. The atomists can be viewed as having hit on a hypothesis for which, two thousand years later, some evidence happened to be found.[26]

         3. Metrodorus

      7. Pherecydes

      8. Sophists

         1. Gorgias

         2. Protagoras

         3. Antiphon

         4. Prodicus

         5. Hippias

         6. Thrasymachus

         7. Callicles

         8. Critias

         9. Lycophron

      9. Diogenes

   2. Classical Greek

      1. Socrates

      2. Euclid of Megara

      3. Plato

      4. Aristotle

      5. Stilpo

   3. Hellenistic

      1. Metrodorus the Younger

      2. Arcesilaus

      3. Archimedes

      4. Clitomachus

      5. Peripateticism

         1. Theophrastus

         2. Strato

         3. Alexander of Aphrodisias

      6. Cyrenaicism

         1. Aristippus of Cyrene

      7. Epicureanism

         1. Epicurus

         2. Metrodorus of Stratonicea

         3. Zeno of Sidon

         4. Philodemus

         5. Lucretius

      8. Stoicism

         1. Zeno of Citium

         2. Cleanthes

         3. Chrysippus

         4. Posidonius

         5. Seneca

         6. Epictetus

      9. Neo-Pythagoreanism

         1. Apollonius of Tyana

         2. Numenius of Apamea

      10. Neo-Platonism

          1. Plotinus

          2. Porphyry

          3. Iamblichus of Chalcis

      11. Pyrrhonism

          1. Pyrrho

          2. Aenesidemus

          3. Timon

      12. Cynicism

          1. Antisthenes

          2. Diogenes of Sinope

          3. Menippus

          4. Crates of Thebes

          5. Demetrius

      13. Philo of Larissa

      14. Philo of Alexandria

      15. Agrippa

      16. Platonism

          1. Speusippus

          2. Carneades

          3. Antiochus of Ascalon

          4. Xenocrates

          5. Plutarch

2. Medieval

   1. Augustine

   2. Boethius

      1. Boethius-foreknowledge.doc

   3. John Scottus Eriugena

   4. Maimonides

   5. Roger Bacon

   6. Anselm of Canterbury

   7. Peter Abelard

   8. Thomas Aquinas

   9. John Duns Scotus

   10. William of Ockham

3. Renaissance

   1. Mirandola

   2. Erasmus

   3. Machiavelli

   4. Thomas More

   5. Paracelsus

   6. Copernicus

   7. Montaigne

4. Early Modern

   1. Francis Bacon

   2. Rene Descartes

   3. Hobbes

   4. Henry More

   5. Arnauld

   6. Malebranche

   7. Benedict Spinoza

   8. Lady Anne Conway

   9. John Locke

   10. Gottfried Leibniz

   11. Berkekey

   12. Wolff

   13. Rousseau

   14. Immanual Kant

   15. Bentham

   16. Schiller

   17. Malthus

5. 19th Century

   1. Johann Fichte

   2. Friedrich Schelling

   3. GWF Hegel

   4. Arthur Schopenhauer

   5. Kierkegaard

   6. Nietsche

   7. Peano

   8. Durkheim

   9. William James

   10. Pareto

   11. Veblen

6. Contemporary

   1. Husserl

   2. Moore

   3. Otto

   4. Ferdinand Saussure

   5. Dewey

   6. Bertrand Russell

   7. Alfred North Whitehead

   8. Santayana

   9. Heidegger

   10. Godel

   11. Gramsci

   12. Popper

   13. Horney

   14. Gilbert Ryle

   15. Wittgenstein

   16. Ayn Rand

   17. Quine

   18. Chomsky

   19. Derrida

   20. John Searle

   21. John Rawls