Today, we are comfortable with the understanding that we live in a dynamic universe that was born 13.7 billion years ago, that consists of innumerable galaxies (at least 200 billion) each comprised of innumerable stars (the Milky Way is estimated to have more than 100 billion stars in it) in an ever-expanding space. This understanding, however, is very recent, having emerged only in the mid-twentieth century to the surprise of most physicists. Indeed, it was only then that the existence of galaxies other than the Milky Way was discovered and the vast extent of the universe was appreciated.
One of the defining features of early Greek philosophical theories was the cosmogony, an account of how our world or cosmos arose in the beginning. These theories came to seem quaint in modern times, until the question of how the universe arose suddenly became a central concern of physics. Most early theories depicted the cosmos as emerging out of chaotic matter by a series of natural processes governed by change encounters producing large structures governed by winds or vortices. Some few early thinkers viewed the cosmos as uncreated and constant—early steady-state theorists.[47] Most, however, recognized some sort of cosmic evolution that achieved a happy equilibrium which produced a stable environment supporting living things, including intelligent beings (humans) who could develop cultures and bodies of knowledge, including philosophy and science. These cosmogonies sometimes hinted at some sort of directing influence, but stressed the operation of chance or natural necessity as the driving cosmic developments. These primitive theories began to seem prescient in light of recent developments in scientific cosmology.
In the Timaeus, Plato tells a creation story about how the cosmos emerged by the agency of the Demiurge, a creator god organizing pre-existing matter according to a formula exhibited in the eternal pattern of the Living Creature. Aristotle takes Plato to be a straightforward creationist.[48] There have, however, been alternative readings of the Timaeus from early times. Perhaps the cosmos has always been in existence, but Plato offers a kind of allegory by which we can see the relationships between the various aspects of the cosmos—the creation story is not to be taken literally but figuratively.[49] This debate continues until the present day.[50]
As one recent commentator has pointed out, Plato argues strongly for a world that has come-to-be at the outset of his cosmology,[51] which precedes his appeal to myth or a likely story.[52] I might also add that the Timaeus account seems to fulfill a need expressed already in the Philebus, to provide a causal explanation for the orderliness of the world.[53] Plato’s argument is that the sensible world is subject to flux or process, so that events in that world are subject also to some cause. Certainty is not possible in this realm, but we can try to provide the most plausible account nonetheless.[54] The orderliness of the world suggests that what is needed is some rational agent: on the principle of garbage in, garbage out, we must suppose order in will lead to order out.
At this point cosmology seems to meet theology: if the cosmos is to proceed from disorder to order, and disorder does not engender order (by a law of entropy), then there must be some pre-existing rational agent that structure the world, a craftsman, designer, creator. That is what Plato now posits as the explanation for the wonderful world we live in. In a society familiar with the Book of Genesis, this theory might be seen as a philosophical interpretation of a scriptural creation story. But in the Greek world, there is no religious model to appeal to—none that offers a creator for the cosmos itself. Here Plato can appeal to the principle he announced in the Phaedrus, that soul is prior to body, with the corollary that mind is prior to matter.[55] If there is rationality in the world, there must be rationality in the maker of the world. Never mind that traditional Greek religion has no place for a transcendent creator god. Such a being must exist, along with the transcendent archetype that he will copy to make the one world.
Plato is working within the framework of the Socratic tradition. Socrates had abandoned cosmology and its related scientific concerns for human studies, and in particular questions of right and wrong, good and evil—ethics and value theory. He saw the good as the goal of all human action and endeavor. Socrates seems to have regarded cosmology as, if not an impediment, at least a distraction from the most important task of philosophy: to identify and promote the good life.
For his part, Plato admired the cosmologist Anaxagoras for saying that in the cosmos Mind ordered all things. But he was disappointed that Anaxagoras did not appeal to reason and purpose in explaining how the cosmos was formed.[56] Anaxagoras’ cosmic Mind started a vortex motion in the primeval matter, and that vortex acted to separate out different kinds of matter like a centrifuge.[57] The cosmos emerged as if by magic, but, as far as Anaxagoras tells us, Mind acted only to initiate the vortex, not to control or fine-tune its outcomes. This account seems to square with Deism, a modern theological theory that has God as creating the world without intervening in its ongoing development.
What Plato offers us is a cosmic Mind that plays an active role in shaping the cosmos, including mixing the cosmic batter that is soul stuff, providing structure for the elements, and designing the shape of the universe. Plato’s Demiurge, the cosmic chef, engineer, and creator, brings into existence the race of gods, whom he then trains to design animal and human bodies and animate them with souls. Plato presents the story of a rational construction of the cosmos, in which the creator organizes his materials in the best way possible and then uses them (or provides them for his divine subordinates) to build the best possible world. The present world will not be ideal, for the materials and creatures in it, and even the heavenly bodies, are made of fallible materials. But the divine engineer and his assistants will attain the optimum results. And their aim is not solely to build a functional world, but to provide a training ground for rational souls to improve themselves and escape from the cycle of rebirths so to return to their homes in the stars.
Only in this way, Plato seems to believe, can cosmology take its place in the world of Socratic humanism. Cosmology must be subordinated to ethics and value theory. If the cosmos exists for the sake and benefit of souls, then cosmology emerges as a worthy object of study. In general, natural science now has a justification, and, purged of chance and mere necessity, it can be restored to the curriculum of philosophy. Natural science supports rational cosmology, and rational cosmology reveals the ethical aim and purpose of the cosmos, the superiority of soul to body, and the divine destiny of soul. Plato’s ideals, taken over from Socrates and supercharged as Forms, have rearranged the curriculum of philosophy. Plato can now put ethics at the pinnacle, with science and cosmology as stepping-stones.
[47] Perhaps Xenophanes (21A32, A33); probably Heraclitus (B30, though some argue for the cosmos undergoing periodic conflagration, as for the Stoics—see Kahn 1979: 134-138); and Melissus (B2, B3).
[48] Aristotle On the Heavens I.10, 280a28-32.
[49] Plutarch On the Generation of the Soul in the Timaeus1012d-1013c traces the view back to Plato’s student Xenocrates.
[50] See Guthrie HGP 5.299-305.
[51] Sedley 2007: 101, commenting on Timaeus 28b-c; Gregory 2007: 151 gives more qualified support for the literal interpretation.
[52] Guthrie HGP 5.305.
[53] Plato Philebus 26e-27c; 28d-e.
[54] Plato Timaeus 29b-d.
[55] Plato Phaedrus 245c-e.
[56] Plato Phaedo 97b-98d.
[57] Anaxagoras B12, B13.