If, however, in the science of nature the Stoics can lay claim to no striking origi nality, the case is different when we come to the science of man. In the rational creatures—man and the gods—Pneuma is mani fested in a high degree of purity and intensity as an emanation from the world-soul, itself an emanation from the primary sub stance of purest ether—a spark of the celestial fire, or, more accurately, fiery breath, which is a mean between fire and air, characterized by vital warmth more than by dryness. The physical basis of Stoic psychology deserves the closest attention. On the one hand, soul is corporeal, else it would have no real existence, would be incapable of extension in three dimensions (and there fore of equable diffusion all over the body), incapable of holding the body together, as the Stoics contended that it does, herein presenting a sharp contrast to the Epicurean tenet that it is the body which confines and shelters the light vagrant atoms of soul. On the other hand, this corporeal thing is veritably and identically reason, mind, and ruling principle (Xlyos, vovs, imuovtK6v), in virtue of its divine origin Cleanthes can say to Zeus, "We too are thy offspring," and a Seneca can calmly insist that, if man and God are not on perfect equality, the superiority rests rather on our side. What God is for the world that the soul is for man. The Cosmos must be conceived as a single whole, its variety being referred to varying stages of condensation in Pneuma. So, too, the human soul must possess absolute sim plicity, its varying functions being conditioned by the degrees or species of its tension. It follows that of "parts" of the soul, as previous thinkers imagined, there can be no question; all that can consistently be maintained is that from the centre of the body—the heart—seven distinct air-currents are discharged to various organs, which are so many modes of the one soul's ac tivity. The ethical consequences of this position will be seen at a later stage. With this psychology is intimately connected the Stoic theory of knowledge. From the unity of soul it follows that all psychical processes—sensation, assent, impulse—proceed from reason, the ruling part ; that is to say, there is no strife or division : the one rational soul alone has sensations, assents to judgments, is impelled towards objects of desire just as much as it thinks or reasons.
In their view of man's social relations the Stoics are greatly in advance of preceding schools. We saw that virtue is a law which governs the universe : that which Reason and God ordain must be accepted as binding upon the particle of reason which is in each one of us. Human law comes into existence when men recognize this obligation; justice is therefore natural and not something merely conventional. The opposite tendencies, to allow to the individual responsibility and freedom, and to demand of him obedience to law, are both fea tures of the system ; but in virtue even of the freedom which belongs to him qua rational, he must recognize the society of rational beings of which he is a member, and subordinate his own ends to the ends and needs of this society. Those who own one law are citizens of one state, the city of Zeus, in which men and gods have their dwelling. In that city all is ordained by reason working intelligently, and the members exist for the sake of one another; there is an intimate connection
between them which makes all the wise and virtuous friends, even if per sonally unknown, and leads them to contribute to one another's good. Their intercourse should find expression in justice, in friendship, in family and political life. But practically the Stoic philosopher always had some good excuse for withdrawing from the narrow political life of the city in which he found himself.
The circumstances of the time, such as the decay of Greek city life, the foundation of large territorial states under absolute Greek rulers which followed upon Alexander's conquests, and afterwards the rise of the world-empire of Rome, aided to develop the lead ing idea of Zeno's Republic. There he had anticipated a state without family life, without law courts or coins, without schools or temples, in which all differences of nationality would be merged in the common brotherhood of man. This cosmopolitan citizenship remained all through a distinctive Stoic dogma; when first announced it must have had a powerful influence upon the minds of men, diverting them from the distractions of almost parochial politics to a boundless vista. There was, then, no longer any difference between Greek and barbarian, between male and female, bond and free.
The religious problem had peculiar interest for the school which discerned God everywhere as the ruler and upholder, and at the same time the law, of the world that He had evolved from Himself. The physical ground-work lends a religious sanc tion to all moral duties, and Cleanthes's noble hymn is evidence how far a system of natural religion could go in providing satis faction for the cravings of the religious temper : "Most glorious of immortals, 0 Zeus of many names, almighty and everlasting, sovereign of nature, directing all in accordance with law, thee it is fitting that all mortals should address. . . . Thee all this universe, as it rolls circling round the earth, obeys wheresoever thou dost guide, and gladly owns thy sway. Such a minister thou holdest in thy invincible hands—the two-edged, fiery, everliving thunderbolt, under whose stroke all nature shudders. No work upon earth is wrought apart from thee, lord, nor through the divine ethereal sphere, nor upon the sea ; save only whatsoever deeds wicked men do in their own foolishness. Nay, thou knowest how to make even the rough smooth, and to bring order out of disorder; and things not friendly are friendly in thy sight. For so hast thou fitted all things together, the good with the evil, that there might be one eternal law over all. . . . Deliver men from fell ignorance. Banish it, father, from their soul, and grant them to obtain wisdom, whereon relying thou rulest all things with justice." To the orthodox theology of Greece and Rome the system stood in a twofold relation, as criticism and rationalism. That the popular religion contained gross errors hardly needed to be pointed out. The forms of worship were known to be trivial or mischievous, the myths unworthy or immoral. But Zeno declared images, shrines, temples, sacrifices, prayers and worship to be of no avail. A really acceptable prayer, he taught, can only have reference to a virtuous and devout mind : God is best worshipped in the shrine of the heart by the desire to know and obey Him. At the same time the Stoics felt at liberty to defend and uphold the truth in polytheism. Not only is the primitive substance God, the one supreme being, but divinity must be ascribed to His mani festations—to the heavenly bodies, which are conceived, like Plato's created gods, as the highest of rational beings, to the forces of nature, even to deified men ; and thus the world was peopled with divine agencies. Moreover, the myths were ra tionalized and allegorized, which was not in either case an orig inal procedure. The search for a deeper hidden meaning beside the literal one had been begun by Democritus, Empedocles, the Sophists and the Cynics. It remained for Zeno to carry this to a much greater extent and to seek out or invent "natural prin ciples" (Xlryot cfmnicoi.) and moral ideas in all the legends and in the poetry of Homer and Hesiod. In this sense he was the pat tern if not the "father" of all such as allegorize and reconcile.