STOICISM is a system of philosophy developed in Greece in the late 4th century b. c. Its later and better-known commentators, who include Emperor Marcus Aurelius (121-180 A.D.), Seneca (about 4 b. c.-65 a. d.) and Cicero (106-43 b. c.) stressed the moral and ethical standards of Stoicism and held the pursuit of virtue as the highest good. However, from the little that is known of early Stoicism, such as its founder, Zeno of Citium ( about 334-262 B.C.), there was an underlying belief in the law of nature and reason called the logos. The con scientious pursuit of virtue advocated by the Stoics was the practical working out of the logos.

             The name Stoic is probably derived from the Painted Stoa, a colonnade ( Greek stoa ) in the marketplace in Athens where Zeno taught soon after his arrival there in 312 b. c.

             The Stoic tradition may be divided into three periods: the Early Stoa, including the period from Zeno down to 129 b. c., wlnen Antipater of Tarsus was succeeded as head of the Stoa at     Athens by Panaetius of Rhodes (about 185-about 109 B.C); the Middle Syoa, including the years 129 b. c. to 30 s. c., the beginning of the Augustan era in Rome; and the New Stoa, which continue to the begining ot the 3d century A.D.

                                                                                    Physics.

The basic concept of Stoic philosophy is logos, a Greek word meaning "reason" or "reasoned speech. " In Stoicism it designated a divine power, penading all things. It is often        referred to as a breath, which in Greek is pneuma, or a seed. To the Stoics it was reality, and divine. Pneuma or logos was held to be the cause of, and to be present in, each quality of an      object. A quality was thought of as anything that defined an object. As Chrysippus wrote, pneuma was called hardness in iron, density in stone, and the white sheen in silver. It permeates both ani mate and inanimate matter. It is mind, soul, na ture, and disposition. As disposition, it is present in bones and sinews and in the earth; as mind, it is found in the intelligence and in the ether.

             Logos, or the qualities in which it was present, was conceived of as either an active or a passive power. Thus, the roundness of a stone might be the cause of the stone's rolling, or a hot object the cauise of heat in another object. On the other hand, the hot might be acted upon by the cold, and the object in which it was present would become cold. This aspect of the Stonic logos explains the interest the Stoics had in the      problem of cause and effect. They conceived of every object or event both as predetermined by a series or chain of causes and as a possible cause of other effects. This ordered series of causes they called fate.

             Since pneuma was believed to pervade all qualities, it followed that there must be an essen tial similarity or oneness between the parts of the universe. The intelligence of man, the breath of air, and the solidity of a stone were all pneuma. It was the Stoic acceptance of this essential one ness, together with their belief in a system of interlocking causes, that led them to accept divination, the foretelling of the future by signs such as weather portents and the flight of birds. There was, they held, a divinable connection be tween such occuirences and future events in human experience.

             This determinism raised problems concerning the Stoic concept of logos, however, for logos was believed to be divine, and if it was to pre serve its divinity it must nOt be dependent upon anytlning external to itself. Hence the independence of logos was asserted in Stoic discussions of possihility of free will. Chrysippus argued that all that is theoretically capable of being, having existence, or occurring, even if it is not going to be, is possible. For example, a stone can be broken, even though it never will be broken. The quality of breakability is part of the lo gos, therefore, regardless of whether the stone should be broken or not. Similarly, in regard to human free will, the legendary Oedipus was said to have been free either to' kill Or nOt to kill his father, in spite of the fact that he had been fated to kill him and did.

             Pneuima was said to be a'°tensional motion" within eacln entity, a stretching or tightness responsible for the entity's coherence, and also to be a movement toward the pneuma external to it. This double aspect of pneuma was used to explain sense perception. In sight, for example, pneurma was held to stretch from the seat of intelligenc'e to the eye with a spherical wavelike motion, while the air between the eye and the object, when illuminated by li ght, was held to take on the quality of pneuma and make the act of sight possible. Thus, the act of vision was attributed to the dynamic power of pneuma, by which presentations of visual objects were transmitted to the intelli gence. As productive of coherence within the soul, pneuma was thought to be responsible for consciousness; as extending toward the peripheral environment, for perception. Within tlne soul a representation awakened an impulse, and in the case of true perception the representation compelled the intelli gence to assent to the impulse, thus providing a basis for distinguishin g genuine perception from illusory perception.

                                                                                                Logic and Rhetoric.

In logic, the Stoics made a significant advance over the Aristotelian system. They developed a theory of signs and a logic of propositions. They seem to have taken five inference scheruas as basic, and to have derived other schemas from these five.

  The Stoic cate gories were four in number: substratum qualified object, disposition, and relative disposition. The first probably desi gnated the genus or species of an object, and the third and fourth cate gories were differentiations or qualifications of substrata and qualified objects. The category "@lisposition" incl@rded any differen tia externolly related to its environment, such as "sweet" or°°red," while "relative disposition" included internally related differentiae suich as "left" or '°father " The system was essentially nomninalistic and' a word as well as an object, conld be analyxed in terms of substratum and differentia.

             The Stoics departed radically from the Platonic scheme for defining objects by continued subdivision of classes that contained the objects. The Stoic method \was based on the disjunctive (either/or ) proposition. Each term in the division added a differentia to the previous term

             In rhetoric, the Stoics recognixed three kinds of speeches: deliberative, forensic, and panegyrical. They held that the ideal speech had four parts: the introduction, statement of the case, refutation of opponents, and the peroration. The Stoics followed Theophrastus in regarding as criteria of excellence the ruse of a pure Greek style, clarity, appropriateness, and constructive reasoning. The Sitoics added to these a fifth criterion, conciseness.

    Ethics and Politics.

The Stoics held that there were basically just two classes of men, the wise, who were virtuous, and the uinwise, who were wicked. However, they also spoke of those individ@uals who were making progress toward virtue. Muich attention was paid to the character of the ideally wise nian by the Early Stoa. Two principles were reco gnized, the independence of the wise man and his responsibility to do ,good.

             The virtuue of the wuse man was held to be suufficient for his happiness, and thus his happiness co@ild not be imipaired by the loss of family, rep@itation, or any other external benefit. So far as his virtue was concerned, the Stoic wise man was independent of the society in which he lived. Yet a nian could become more virtuuous only by exercusung hus vurtue in his relations with other men, and the exercise of virtue was to be found in areas demandin g responsibility. Thus it was necessary for hini to earn his living, support his family, :and take part in public life. Zeno regarded actions of this kind as duties, "acts of which a reasonable acco@int can be given."

             Simiplicity and frugality played an important role in Stoic ethics. In the Early Stoa this took the formi of contempt for social convention. Zeno, in his Republic, arg@@ed that the citizens of his state wouild not build temples, since the work of builders and craftsmen was neither of true value nor sacred. He refused to allow either coinage or law courts in his ideal city. Both Zeno and Chrysippuis opposed conventional marriage and advocated the community of women.

             More significant was the ennphasis the Stoics placed on the essential kinship of all men throu@gh their participation in divune reason, or logos. They spoke of a universal society, a kind of brotherhood of mankind, transcending the state. They refuised to attach any si gnificance to noble birth and showed concern about the position of the slave. Chrysippus defined the slave as a "hired nian for life," suggesting thereby that he regarded the slave as a man doing a piece of work b@ut by nature not different from his master.

             The early Stoics all showed interest in poli tics. Both Zeno and Chrysippus wrote books entitled Tlae Republic. Zeno's disciples Persaeus Sphaerus, and Cleanthes wrote treatises called

 Conceriuny Kingslup. CLirysippus argued that the life for which the wise nian was most suited was that of a statesman. They had connections with contemporary r@ulers. Zeno was visited by

 Autigonus Gonatas, the king of Macedon, and sent one of his pupils, Persaeus, to the King's co@urt. Another pupil, Sphaerus, was the tutor and adviser of King Cleomenes of Sparta, who attempted economic reforms based on land dis tribution and abolition of debts, and advocated a return to an old-fashioned simplicity of life.

                  EARLY STOA

The evidence for the dates of the philosophers of the Early Stoa ( 300-129 s. c. ) is skimpy and unreliable. In some cases the ancient tradition cannot give us much more than an approxima tion; in others, we know the date of a sin gle event un the rhulosopher's life. Aristo of Chios was prominent in the first half of the 3d century B. C.; Persaeus of Citium was born about 306 e. c.  and lived until at leasr 243 a. c.; Sphaerus, who

 came from the Bosporus, was at the court of Cleomenes, King of Sparta, from about 236 to  222 B. c.; Cleanthes of Assos probably lived From about 331 to 232, B.C. chrysippus, from Soloi in Cilicia, died between 208 and 204 B. c. Diogenes of Babylon visited Rome in 155 B. c.; and Antipater of Tarsus was in Rome before 133 B. c.

             Much work remains to be done on the in fluence of other philosophic schools on early Stoicism, but Stoicism undoubtedly grew through contact with the other schools in Athens. Zeno       hinmself was a Phoenician who established his own school in Athens after he had studied there with Crates, a Cynic; Stilpo, a Megarian; and kenocrates and Polemon, both of whom be longed to the Platonic Academy. In addition, he was contemporary u'ith Epicurus, who established his school, the Garden, about 300 s. c., and with the Peripatetic philosopher Theophrastus ( about     370-about 287 e. c. ).

                         MIDDLE STOA

             With the Middle Stoa ( 129-30 e. c. ) the scene of Stoic influence shifted from Athens io Rome. P'anaetius of Rhodes, who succeeded Antipater of Tarsus as head of the Stoa in 129 b. c., was in Rome at least as early as 140 b. c. He u-as a friend of Scipio Africanus, an out standing geineral and leading aristocrat. Panae tius' pupil Hecaton of Rhodes was a friend of    L. Aelius Tubero, who was a candidate for the praetorship in 129 e. c. Blo'ssius of Cumae was  the associate of the Roman statesman Tiberius C,racchus in 134 s. c., and Posidonius of Rhodes visited Rome in 87 and 51 s. c. By their associa tions with the statesmen of Rome, these philos ophers strongly influenced Roman public life.

             Panaetius'philosophy was practical and mat ter-of-fact. He rejected the possibility that a man nmight attain perfect wisdom and argued that virtue was not sufficient for happiness. If, as    seenms probable, he is the source of the first two books of Cicero's De officiis, we must attribute to him Cicero's discussion of decorum as a virtue. The Latin word decorum means "that which is fittirmg or appropriate." According to the passage in question, we must consider the nature of the individual, his position, wealth, and age if we are to discover whether an action is fitting o'r not. The whole passage suggests an emphasis on con formity and convention alien to,the Early Stoa.

             The first book of the De officiis contains an interesting definition of justice. According to this definition,justice requires us not only to avoid injuring another person, but also to take steps to ensure that an innocent person will not receive

injury at the hands of another. Thus a passive acquiescence to a wrong is itself a moral wrong. The same high standards are shown in the dis cussion of a defeated enenmy, where it is argued that tlhe lives of enemies who have shown no cruelty should be spared and that, while the guiilty must be punished, the mass of an enemy population shouild be protected. Man's duty to takP part in public life is emphasized.

             Posidonius of Rhodes has been regarded by some as the father of Neoplatonism. Although there is little in his philosophy to support this interpretation, there are such significant differ encs between his philosophy and that of the     other Stoics that it is misleading to quote his writings, which are available only in fragments, as representative of Stoicism. Among his atypical views were his rejection of the existence of un quialified matter and his argument that God did not create the world buit adapted himself to that which already existed. Both of these theoires were heretical in terms of the Early Stoa. He seems also to have denied the immortality of the soul, and to have identified it with a geometrical figure.

                                                                     NEW STOA

             The chief figures of the New Stoa ( 30 B. C.200 A. n. ) are Seneca, Musonius Rufus, Epictetus, and Marcus Aurelius. All four philosophers were interested chiefly in ethics, which by this time had lost much of the rugged nonconformity of the Early Stoa. They offered sound pratical advice to the young Roman nobility.

             Throughout the Ist century A. n. the Stonic took a firm stand against the excesses and outrages of t.he Roman emperors. Their protests frequently found expression in suicide, since this was regarded by the Stoics as an honorable release for those who could no lOnget fulfill their duties in life. Seneca, who had been the tutor of Nero, was accused of being involved in the Pisonian conspiracy in 65 A. n. and was requested to commit suicide. Musonius was exiled by Nero in 65 A. n. to' the island of Gyaros in the Cyclades. He returned to Rome when Nero died in 68 but again suffered exile under Vespasian. He was recalled to Rome by Titus between 79 and 81 A. n. Similarly Epictetus was banished by Domitian in 90 A. n., and retired to Nicopolis in  Epirus. U'ith the advent of Marcuis Aurelius as emperor, Stoicism once again came into its own.  By the middle of the 3d century, however, it had almost entirely disappeared, hav-ing been replaced by Neoplatonism and Christianity.

                                                                                    Stoicism and Early Christianity.

Stoicism influenced Christianity in many respects. Christians converted from Stoicism expressed their new ideas in Stoic terms. Thus the term "logos" is found in the first verse of St. John's Gospel where it is translated as '@U'ord": "In the beginnin was the U'ord, and the U'ord was with God, and the U'ord was God." In St. John 4:24 God is called a spirit or in Greek, pneuma. Both "logos" and "pneuma," however, had taken on new meanings consistent with Christian doctrine and reflecting as well the Judaic origins of Christianity. The Stoic belief that the world would eventuially be destroyed by fire agreed well with the Christian doctrine of the Last Judgment. The Stoics had emphasized the essential similarity of all men and the moral responnsi bility of each man to p vide for the basic needs of other men. -ey h insisted on simplicity and frugality and on the independence of the individual in the face of an evil and hostile society. All of these teachings were in harmony with Christianity. It is not surprising, therefore, to find traces of Stoic philosophy in Tertullian. Clement of Alexandria, Origen, Lactantius, St Am brose, St. Augustine, and other Christian writers.

                                                                                                            Later Innuence of Stoicism.

In the 16th and 17th centuries interest in Stoicism revived. Seneca's plays exerted a strong influence on the English drama of that period. Justus Lipsius of the Netherlands attempted to state the essence of Stoic philosophy in his Manuductio ad Stoicam philosophiam ( 1604 ) and his Physiologia Stoicorum ( 1610 j. Herbert of Cherbury in his De veritate ( 1624 ) drew upon Stoic theories of knowledge. Baruch Spinoza in the 17th century and Immanuel Kant in the 18th used Stonic theories in metaphysics and ethics, respectivlty. In the mid-20th century Stoic logic has received considerable attention from symbolir logicians.