The holistic theory of the cosmos, advanced by Thales of Miletus (c. 624–c. 546 BC) and Anaximenes of Miletus (c. 585–c. 528 BC), became a basic tenet of Greek philosophy (see Introduction). The following writings indicate the same:
Anaximander of Miletus (c. 610–c. 546 BC):
The Infinite (apeiron) . . . eternal and ageless . . . is the cause (arche) and first element (stoicheion) of things . . . from which arise all the heavens and the worlds within them. . . . And into that from which things take their rise they pass away once more.
[Anaximander, Fragments, in Early Greek Philosophy, quoted by Theophrastus and Simplicius, translated by John Burnet (London: Adam and Charles Black, 1930), p. 52.]
Pherecydes of Syros (c. 580–c. 520 BC):
Divine Love created the cosmos. Putting together the cosmos from opposites, he brought it into harmony and love, and sowed likeness in all things and oneness pervading the whole.
[Pherecydes, Fragments, in Pherekydes of Syros, quoted by Proclus, translated by Hermann Schibli (Oxford: Clarendon Press, 1990), p. 168.]
Xenophanes of Colophon (c. 570–c. 475 BC):
There is one god (theos), among gods and men the greatest, not at all like mortals in body or in mind. He sees as a whole, thinks as a whole, and hears as a whole.
[Xenophanes, Fragments, in Ancilla to the Pre-Socratic Philosophers, quoted by Clement and Sextus Empiricus, translated by Kathleen Freeman (Cambridge: Harvard University Press, 1962), p. 23; Hermann Diels, Die Fragmente der Vorsokratiker (Berlin: Weidmann, 1964), p. 135.]
Heraclitus of Ephesus (c. 535–c. 475 BC):
When you have listened, not to me but to the Logos (ultimate reason), it is wise to agree that all things are one.
Heraclitus and other Presocratic philosophers further insisted that things in seeming opposition actually intertwine as one. One of Heraclitus’ analogies stated:
The way up and down is one and the same.
[Heraclitus, Fragments, in Ancilla to the Pre-Socratic Philosophers, quoted by Hippolytus, translated by Kathleen Freeman (Cambridge: Harvard University Press, 1962), pp. 28–29; Diels, Die Fragmente der Vorsokratiker, pp. 161, 164.]
Universal oneness remained a common theme of the Presocratic Philosophers. They used various descriptors for the infinite, indefinable One. These included Hesiod’s Chaos (meaning undefined or formless), Anaximander’s Infinite (apeiron), Pherecydes’ Divine Love (eros), Xenophanes’ God (theos), Heraclitus’ Ultimate Reason (logos), Parmenides’ Being (einai), and Anaxagoras’ Mind (nous). These philosophers, along with Melissus, Empedocles, Philolaus, and Diogenes, spoke often of the One and the Whole.
The three Athenian philosophers—Socrates (c. 469–399 BC), Plato (c. 424–c. 348 BC), and Aristotle (384–322 BC)—agreed with their predecessors that there existed one eternal, primal source, which was an intangible and indescribable spirit. Plato called this spirit agathos—the good. He provided a fine example of this aspect of Presocratic and Socratic thought in his Allegory of the Cave. [Plato, The Republic, translated by Paul Shorey (Cambridge: Harvard University Press, 1970), sections 514–518.]
Even though this spirit was indescribable in human terms, the Athenian philosophers asserted that awareness of it remained within reach of persons possessing exceptional insight. For them, it was possible to transcend the superficialities and anxieties of the world, in their lifetime, and gain a glimpse of the good. Further, they believed the good would become fully evident in the eternal life that followed.
Socrates said that those who keep their minds fixed on the good of the spiritual realm need not fear—for no lasting “evil can happen, either in life or in death.” He believed that the world was transitory and the human body perishable, but that the spirit within was immortal and bound for a higher existence. Consequently, he pleaded with his grieving students, at the time of his execution, to:
Be of good cheer . . . and say that you are burying my body only.
[Plato, Phaedo, in The Dialogues of Plato, translated by B. Jowett (New York: Random House, 1937), section 116. Socrates left no written records, but Plato often quoted him, and provided insight into the mind of his famous mentor.]
Socrates’ student—Plato—expanded upon his teachings by stressing the spiritual nature of reality. The world, he said, is but a dim, deficient shadow; so the worthiest human endeavor is to seek the spiritual realm. Humans inherently yearned for this, but to reach it required transcending worldly distractions. One needed to shun the pursuit of power, possessions, and selfish strife. Instead, one should live simply, in peace, while seeking the spiritual good. Plato wrote:
My dream, as it appears to me, is that . . . the idea of good (agathos) . . . is indeed the cause for all things—of all that is right and beautiful, giving birth in the visible world to light and the author of light [the sun]; And itself in the intelligible world being the authentic source of truth and reason; And that anyone who is to act wisely in private or public must have caught sight of this. . . . That those who have attained to this height are not willing to occupy themselves with the affairs of men, but their souls ever feel the upward urge and the yearning for that sojourn above.
[Plato, Republic, section 517.]
When a man is always occupied with the cravings of desire and ambition, and is eagerly striving to satisfy them, all his thoughts must be mortal. . . . But he who has been earnest in the love of knowledge and of true wisdom . . . since he is ever cherishing the divine power, and has the divinity within him in perfect order, he will be perfectly happy.
[Plato, Timaeus, section 90.]
Plato’s student—Aristotle—added that the physical world should not be neglected in favor of the spiritual realm. After all, the divine spirit is tangible in the natural world just as it is intangible in the human mind and soul. The physical and spiritual universe are one harmonious whole. Aristotle said:
God (theos) is the first principle, upon which depends the sensible [sensory] universe and the world of nature. . . . We hold then that God is a living being, eternal, most good; and therefore life and a continuous eternal existence belong to God; for that is what God is.
[Aristotle, Metaphysics, translated by Hugh Tredennick (Cambridge: Harvard University Press, 1947), section 12.7.7–9.]
This supreme good encompasses the cosmos and is also the orderly arrangement of its parts. . . . Thus, everything is ordered together to one end, and everything contributes to the good of the whole.
[Aristotle, Metaphysics, 12.10.1–4.]