(19) The Megarians are occasionally included among the dialectic philosophers. Euclid (who died 374? B.C.) was succeeded in his school by Eubulides, among whose disciples were Alexinus and Apollonius Cronus. Euphantus, who lived to great age and wrote many tragedies, was among the foremost followers of Eubulides. Diodorus is usually included in the Megarian school, having heard Eubulides lecture. According to legend, Diodorus died of grief because he could not answer instantly certain questions asked him by Stilpo, at one time master of the Megarian school. Diodorus held that nothing

(12) The Eleatic sect was founded by Xenophanes (570-480 B.C.), who was conspicuous for his attacks upon the cosmologic and theogonic fables of Homer and Hesiod. Xenophanes declared that God was "one and incorporeal, in substance and figure round, in no way resembling man; that He is all sight and all hearing, but breathes not; that He is all things, the mind and wisdom, not generate but eternal, impassible, immutable, and rational." Xenophanes believed that all existing things were eternal, that the world was without beginning or end, and that everything which was generated was subject to corruption. He lived to great age and is said to have buried his sons with his own hands. Parmenides studied under Xenophanes, but never entirely subscribed to his doctrines. Parmenides declared the senses to be uncertain and reason the only criterion of truth. He first asserted the earth to be round and also divided its surface into zones of hear and cold.

(2) Moreover, some time after, Aresas Lucanus, being saved through certain strangers, undertook the management of the school; and to him came Diodorus Aspendius, who was received into the school, on account of the paucity of the Pythagoreans it contained. And in Heraclea, indeed, were Clinias and Philolaus; but at Metapontum, Theorides and Eurytus; and at Tarentum Archytas. It is also said that Epicharmus was one of the foreign auditors; but that he was not one of the school. Having however arrived at Syracuse, he abstained from philosophizing openly, on account of the tyranny of Hiero. But he inserted the conceptions of the men in metre, and published in comedies the occult dogmas of Pythagoras.

(11) After Pythagoras of Samos, its founder, the Italic or Pythagorean school numbers among its most distinguished representatives Empedocles, Epicharmus, Archytas, Alcmæon, Hippasus, Philolaus, and Eudoxus. Pythagoras (580-500? B.C.) conceived mathematics to be the most sacred and exact of all the sciences, and demanded of all who came to him for study a familiarity with arithmetic, music, astronomy, and geometry. He laid special emphasis upon the philosophic life as a prerequisite to wisdom. Pythagoras was one of the first teachers to establish a community wherein all the members were of mutual assistance to one another in the common attainment of the higher sciences. He also introduced the discipline of retrospection as essential to the development of the spiritual mind. Pythagoreanism may be summarized as a system of metaphysical speculation concerning the relationships between numbers and the causal agencies of existence. This school also first expounded the theory of celestial harmonics or "the music of the spheres." John Reuchlin said of Pythagoras that he taught nothing to his disciples before the discipline of silence, silence being the first rudiment of contemplation. In his Sophist, Aristotle credits Empedocles with the discovery of rhetoric. Both Pythagoras and Empedocles accepted the theory of transmigration, the latter saying: "A boy I was, then did a maid become; a plant, bird, fish, and in the vast sea swum." Archytas is credited with invention of the screw and the crane. Pleasure he declared to be a pestilence because it was opposed to the temperance of the mind; he considered a man without deceit to be as rare as a fish without bones.

(23) Diogenes of Sinopis is remembered chiefly for the tub in the Metroum which for many years served him as a home. The people of Athens loved the beggar-philosopher, and when a youth in jest bored holes in the tub, the city presented Diogenes with a new one and punished the youth. Diogenes believed that nothing in life can be rightly accomplished without exercitation. He maintained that everything in the world belongs to the wise, a declaration which he proved by the following logic: "All things belong to the gods; the gods are friends to wise persons; all things are common amongst friends; therefore all things belong to the wise." Among the Cynics are Monimus, Onesicritus, Crates, Metrocles, Hipparchia (who married Crates), Menippus, and Menedemus.

(17) The Elean sect was founded by Phædo of Elis, a youth of noble family, who was bought from slavery at the instigation of Socrates and who became his devoted disciple. Plato so highly admired Phædo's mentality that he named one of the most famous of his discourses The Phædo. Phædo was succeeded in his school by Plisthenes, who in turn was followed by Menedemus. Of the doctrines of the Elean sect little is known. Menedemus is presumed to have been inclined toward the teachings of Stilpo and the Megarian sect. When Menedemus' opinions were demanded, he answered that he was free, thus intimating that most men were enslaved to their opinions. Menedemus was apparently of a somewhat belligerent temperament and often returned from his lectures in a badly bruised condition. The most famous of his propositions is stated thus: That which is not the same is different from that with which it is not the same. This point being admitted, Menedemus continued: To benefit is not the same as good, therefore good does not benefit. After the time of Menedemus the Elean sect became known as the Eretrian. Its exponents denounced all negative propositions and all complex and abstruse theories, declaring that only affirmative and simple doctrines could be true.

(18) The Megarian sect was founded by Euclid of Megara (not the celebrated mathematician), a great admirer of Socrates. The Athenians passed a law decreeing death to any citizen of Megara found in the city of Athens. Nothing daunted, Euclid donned woman's clothing and went at night to study with Socrates. After the cruel death of their teacher, the disciples of Socrates, fearing a similar fate, fled to Megara, where they were entertained with great honor by Euclid. The Megarian school accepted the Socratic doctrine that virtue is wisdom, adding to it the Eleatic concept that goodness is absolute unity and all change an illusion of the senses. Euclid maintained that good has no opposite and therefore evil does not exist. Being asked about the nature of the gods, he declared himself ignorant of their disposition save that they hated curious persons.

(13) Melissus, who is included in the Eleatic school, held many opinions in common with Parmenides. He declared the universe to be immovable because, occupying all space, there was no place to which it could be moved. He further rejected the theory of a vacuum in space. Zeno of Elea also maintained that a vacuum could not exist. Rejecting the theory of motion, he asserted that there was but one God, who was an eternal, ungenerated Being. Like Xenophanes, he conceived Deity to be spherical in shape. Leucippus held the Universe to consist of two parts: one full and the other a vacuum. From the Infinite a host of minute fragmentary bodies descended into the vacuum, where, through continual agitation, they organized themselves into spheres of substance.

(37) "(1) Sense is never deceived; and therefore every sensation and every perception of an appearance is true. (2) Opinion follows upon sense and is superadded to sensation, and capable of truth or falsehood, (3) All opinion attested, or not contradicted by the evidence of sense, is true. (4) An opinion contradicted, or not attested by the evidence of sense, is false." Among the Epicureans of note were Metrodorus of Lampsacus, Zeno of Sidon, and Phædrus.

(1) The successor, however, of Pythagoras, is acknowledged by all men to have been Aristæus, the son of Damophon the Crotonian, who existing at the same time as Pythagoras, was seven ages prior to Plato. Aristæus likewise, was not only thought worthy to succeed Pythagoras in his school, but also to educate his children, and marry his wife Theano, because he was eminently skilled in the Pythagoric dogmas. For Pythagoras himself is said to have taught in his school, forty years wanting one, and to have lived nearly one hundred years. But Aristæus, when much advanced in years, relinquished the school; and after him Mnesarchus succeeded, who was the son of Pythagoras. Bulagoras succeeded Mnesarchus, in whose time it happened that the city of the Crotonians was plundered. Gartydas the Crotonian succeeded Bulagoras, on his return from a journey which he had undertaken prior to the war. Nevertheless on account of the calamity of his country, he suffered so much anxiety, as to die prematurely through grief. But it was the custom with the rest of the Pythagoreans, when they became very old, to liberate themselves from the body as from a prison.

(28) After the death of Plato, his disciples separated into two groups. One, the Academics, continued to meet in the Academy where once he had presided; the other, the Peripatetics, removed to the Lyceum under the leadership of Aristotle (384-322 B.C.). Plato recognized Aristotle as his greatest disciple and, according to Philoponus, referred to him as "the mind of the school." If Aristotle were absent from the lectures, Plato would say: "The intellect is not here." Of the prodigious genius of Aristotle, Thomas Taylor writes in his introduction to The Metaphysics:

(3) Of all the Pythagoreans, however, it is probable that many are unknown and anonymous. But the following are the names of those that are known and celebrated: Of the Crotonians, Hippostratus, Dymas, Ægon, Æmon, Sillus, Cleosthenes, Agelas, Episylus, Phyciadas, Ecphantus, Timæus, Buthius, Eratus, Itmæus, Rhodippus, Bryas, Evandrus, Myllias, Antimedon, Ageas, Leophron, Agylus, Onatus, Hipposthenes, Cleophron, Alcmæon, Damocles, Milon, Menon. Of the Metapontines, Brontinus, Parmiseus, Orestadas, Leon, Damarmenus, Æneas, Chilas, Melisias, Aristeas, Laphion, Evandrus, Agesidamus, Xenocades, Euryphemus, Aristomenes, Agesarchus, Alceas, Xenophantes, Thraseus, Arytus, Epiphron, Eiriscus, Megistias, Leocydes, Thrasymedes, Euphemus, Procles, Antimenes, Lacritus, Damotages, Pyrrho, Rhexibius, Alopecus, Astylus, Dacidas, Aliochus, Lacrates, Glycinus. Of the Agrigentines, Empedocles. Of the Eleatæ, Parmenides. Of the Tarentines, Philolaus, Eurytus, Archytas, Theodorus, Aristippus, Lycon, Hestiæus, Polemarchus, Asteas, Clinias, Cleon, Eurymedon, Arceas, Clinagoras, Archippus, Zopyrus, Euthynus, Dicæarchus, Philonidas, Phrontidas, Lysis, Lysibius, Dinocrates, Echecrates, Paction, Acusiladas, Icmus, Pisicrates, Clearatus.

(34) The sect of the Stoics was founded by Zeno (340-265 B.C.), the Cittiean, who studied under Crates the Cynic, from which sect the Stoics had their origin. Zeno was succeeded by Cleanthes, Chrysippus, Zeno of Tarsis, Diogenes, Antipater, Panætius, and Posidonius. Most famous of the Roman Stoics are Epictetus and Marcus Aurelius. The Stoics were essentially pantheists, since they maintained that as there is nothing better than the world, the world is God. Zeno declared that the reason of the world is diffused throughout it as seed. Stoicism is a materialistic philosophy, enjoining voluntary resignation to natural law. Chrysippus maintained that good and evil being contrary, both are necessary since each sustains the other. The soul was regarded as a body distributed throughout the physical form and subject to dissolution with it. Though some of the Stoics held that wisdom prolonged the existence of the soul, actual immortality is not included in their tenets. The soul was said to be composed of eight parts: the five senses, the generative power, the vocal power, and an eighth, or hegemonic, part. Nature was defined as God mixed throughout the substance of the world. All things were looked upon as bodies either corporeal or incorporeal.

(16) The principles of all things he conceived to be three in number: God, matter, and ideas. Of God he said: "What He is I know not; what He is not I know." Matter he defined as the subject of generation and corruption; idea, as an incorruptible substance--the intellect of God. Wisdom he considered the sum of the virtues. Among the prominent members of the Socratic sect were Xenophon, Æschines, Crito, Simon, Glauco, Simmias, and Cebes. Professor Zeller, the great authority on ancient philosophies, has recently declared the writings of Xenophon relating to Socrates to be forgeries. When The Clouds of Aristophanes, a comedy written to ridicule the theories of Socrates, was first presented, the great Skeptic himself attended the play. During the performance, which caricatured him seated in a basket high in the air studying the sun, Socrates rose calmly in his seat, the better to enable the Athenian spectators to compare his own unprepossessing features with the grotesque mask worn by the actor impersonating him.

(36) Epicurus of Samos (341-270 B.C.) was the founder of the Epicurean sect, which in many respects resembles the Cyrenaic but is higher in its ethical standards. The Epicureans also posited pleasure as the most desirable state, but conceived it to be a grave and dignified state achieved through renunciation of those mental and emotional inconstancies which are productive of pain and sorrow. Epicurus held that as the pains of the mind and soul are more grievous than those of the body, so the joys of the mind and soul exceed those of the body. The Cyrenaics asserted pleasure to be dependent upon action or motion; the Epicureans claimed rest or lack of action to be equally productive of pleasure. Epicurus accepted the philosophy of Democritus concerning the nature of atoms and based his physics upon this theory. The Epicurean philosophy may be summed up in four canons:

(33) Of Skepticism as propounded by Pyrrho of Elis (365-275 B.C.) and by Timon, Sextus Empiricus said that those who seek must find or deny they have found or can find, or persevere in the inquiry. Those who suppose they have found truth are called Dogmatists; those who think it incomprehensible are the Academics; those who still seek are the Skeptics. The attitude of Skepticism towards the knowable is summed up by Sextus Empiricus in the following words: "But the chief ground of Skepticism is that to every reason there is an opposite reason equivalent, which makes us forbear to dogmatize." The Skeptics were strongly opposed to the Dogmatists and were agnostic in that they held the accepted theories regarding Deity to be self-contradictory and undemonstrable. "How," asked the Skeptic, "can we have indubitate knowledge of God, knowing not His substance, form or place; for, while philosophers disagree irreconcilably on these points, their conclusions cannot be considered as undoubtedly true?" Since absolute knowledge was considered unattainable, the Skeptics declared the end of their discipline to be: "In opinionatives, indisturbance; in impulsives, moderation; and in disquietives, suspension."

(14) The great Democritus to a certain degree enlarged upon the atomic theory of Leucippus. Democritus declared the principles of all things to be twofold: atoms and vacuum. Both, he asserted, are infinite--atoms in number, vacuum in magnitude. Thus all bodies must be composed of atoms or vacuum. Atoms possessed two properties, form and size, both characterized by infinite variety. The soul Democritus also conceived to be atomic in structure and subject to dissolution with the body. The mind he believed to be composed of spiritual atoms. Aristotle intimates that Democritus obtained his atomic theory from the Pythagorean doctrine of the Monad. Among the Eleatics are also included Protagoras and Anaxarchus.

(4) Of the Leontines, Phrynichus, Smichias, Aristoclidas, Clinias, Abroteles, Pisyrrhydus, Bryas, Evandrus, Archemachus, Mimnomachus, Achmonidas, Dicas, Carophantidas. Of the Sybarites, Metopus, Hippasus, Proxenus, Evanor, Deanax, Menestor, Diocles, Empedus, Timasius, Polemæus, Evæus, Tyrsenus. Of the Carthaginians, Miltiades, Anthen, Odius, Leocritus. Of the Parians, Æetius, Phænecles, Dexitheus, Alcimachus, Dinarchus, Meton, Timæus, Timesianax, Amærus, Thymaridas. Of the Locrians, Gyptius, Xenon, Philodamus, Evetes, Adicus, Sthenonidas, Sosistratus, Euthynus, Zaleucus, Timares. Of the Posidonians, Athamas, Simus, Proxenus, Cranous, Myes, Bathylaus, Phædon. Of the Lucani, Ocellus and Occillus who were brothers, Oresandrus, Cerambus, Dardaneus, Malion. Of the Ægeans, Hippomedon, Timosthenes, Euelthon, Thrasydamus, Crito, Polyctor. Of the Lacones, Autocharidas, Cleanor, Eurycrates. Of the Hyperboreans, Abaris. Of the Rheginenses, Aristides, Demosthenes, Aristocrates, Phytius, Helicaon, Mnesibulus, Hipparchides, Athosion, Euthycles, Opsimus. Of the Selinuntians, Calais.

Of the Syracusans, Leptines, Phintias, Damon. Of the Samians, Melissus, Lacon, Archippus, Glorippus, Heloris, Hippon, Of the Caulonienses, Callibrotus, Dicon, Nastas, Drymon, Xentas. Of the Phliasians, Diocles, Echecrates, Polymnastus, Phanton. Of the Sicyonians, Poliades, Demon, Sostratius, Sosthenes. Of the Cyrenæans, Prorus, Melanippus, Aristangelus, Theodorus. Of the Cyziceni, Pythodorus, Hipposthenes, Butherus, Xenophilus. Of the Catanæi, Charondas, Lysiades. Of the Corinthians, Chrysippus. Of the Tyrrhenians, Nausitheus. Of the Athenians, Neocritus. And of Pontus, Lyramnus. In all, two hundred and eighteen. [And these, indeed, are not all the Pythagoreans, but of all of them they are the most famous. ]

(4) There was, however, a certain person named Hippomedon, an Ægean, a Pythagorean and one of the Acusmatici, who asserted that Pythagoras gave the reasons and demonstrations of all these precepts, but that in consequence of their being delivered to many, and these such as were of a more sluggish genius, the demonstrations were taken away, but the problems themselves were left. Those however of the Pythagoreans that are called Mathematici , acknowledge that these reasons and demonstrations were added by Pythagoras, and they say still more than this, and contend that their assertions are true, but affirm that the following circumstance was the cause of the dissimilitude. Pythagoras, say they, came from Ionia and Samos, during the tyranny of Polycrates, Italy being then in a florishing condition; and the first men in the city became his associates.

But, to the more elderly of these, and who were not at leisure [for philosophy], in consequence of being occupied by political affairs, the discourse of Pythagoras was not accompanied with a reasoning process, because it would have been difficult for them to apprehend his meaning through disciplines and demonstrations; and he conceived they would nevertheless be benefited by knowing what ought to be done, though they were destitute of the knowledge of the why : just as those who are under the care of physicians, obtain their health, though they do not hear the reason of every thing which is to be done to them. But with the younger part of his associates, and who were able both to act and learn,—with these he conversed through demonstration and disciplines.

These therefore are the assertions of the Mathematici, but the former, of the Acusmatici. With respect to Hippasus however especially, they assert that he was one of the Pythagoreans, but that in consequence of having divulged and described the method of forming a sphere from twelve pentagons, he perished in the sea, as an impious person, but obtained the renown of having made the discovery. In reality, however, this as well as every thing else pertaining to geometry, was the invention of that man ; for thus without mentioning his name, they denominate Pythagoras. But the Pythagoreans say, that geometry was divulged from the following circumstance: A certain Pythagorean happened to lose the wealth which he possessed; and in consequence of this misfortune, he was permitted to enrich himself from geometry.

But geometry was called by Pythagoras Historia . And thus much concerning the difference of each mode of philosophising, and the classes of the auditors of Pythagoras. For those who heard him either within or without the veil, and those who heard him accompanied with seeing, or without seeing him, and who are divided into interior and exterior auditors, were no other than these. And it is requisite to arrange under these, the political, economic and legislative Pythagoreans.

(24) The Cyrenaic sect, founded by Aristippus of Cyrene (435-356? B.C.), promulgated the doctrine of hedonism. Learning of the fame of Socrates, Aristippus journeyed to Athens and applied himself to the teachings of the great Skeptic. Socrates, pained by the voluptuous and mercenary tendencies of Aristippus, vainly labored to reform the young man. Aristippus has the distinction of being consistent in principle and practice, for he lived in perfect harmony with his philosophy that the quest of pleasure was the chief purpose of life. The doctrines of the Cyrenaics may be summarized thus: All that is actually known concerning any object or condition is the feeling which it awakens in man's own nature. In the sphere of ethics that which awakens the most pleasant feeling is consequently to be esteemed as the greatest good. Emotional reactions are classified as pleasant or gentle, harsh, and mean. The end of pleasant emotion is pleasure; the end of harsh emotion, grief; the end of mean emotion, nothing.