Whatever the theological or cosmological status of the Demiurge, he is the Architect and Contractor of the cosmos, and he has a blueprint: the Living Creature, a kind of conglomeration of the Forms that seems to present them in organic connection with one another.
From the outset, Timaeus tells us that the Architect is subject to a kind of natural law: “It neither was nor is lawful (themis) for the best being to produce anything but what is most perfect. As he investigated the matter, he discovered that among things naturally visible nothing that was as a whole irrational could ever be superior to what was a rational product; and that nothing that did not have a soul could have a mind. Accordingly, he joined soul to body to construct the universe so as to produce what was by nature the fairest and best creation. Thus, according to the plausible account, we must say that this world is an animate rational creature truly created through the providence of God.”[1]
Plato’s cosmos will not be an inanimate conglomeration of elements and compounds, but it will be composed—as a whole—of body and soul, including that part of soul that is rational: the mind. There is, then, from the beginning a divine design here, whereby the cosmos will be itself a living creature, modeled after the Living Creature that apparently includes all the Forms in their interconnectedness and perfection.
Reason dictates, according to Timaeus, that there be only one cosmos comprising all physical objects in one as does the Living Creature that is the prototype.[2] In order to have the necessary physical foundation, the Architect needed fire to make things visible, and earth to provide solidity. (According to Aristotle’s reading, fire and earth are the physical manifestations of Parmenides’ Light and Night, so are we following Parmenides’ cosmology?) But in order to join fire and earth, we need intermediate elements, namely water and air, which gives us the four elements that had become standard since the time of Empedocles, and joined them by Friendship.[3] (Later, Timaeus will consider the microstructure of the four elements.) The Architect proceeded to give the cosmos the perfect shape, a sphere, to contain all things (another legacy of Parmenides?).
In order to animate the world, the Architect mixes together the components of soul in a cosmic mixing bowl. The components are Being, Same and Different, which have been identified in the Sophist as among the highest kinds. He weaves soul into the body of the cosmos and makes some of it into circular strands that will be the orbits of the heavenly bodies.[4] The heavenly bodies are made to move with their own motions. By those motions they give rise to time and its measurement in years, months, days and so on.[5]
The Olympian gods arise by some sort of theogony like that described by the poet Hesiod. The Architect turns over to them the responsibility of creating bodies for humans, which they do with an aim to make humans as godlike as possible. The head is made roughly spherical to contains the circles of thought; it is mounted on an upright body with two legs and two arms, to move as close to heaven as possible.[6] The human body is given the five senses so that it may operate in the world.
The Architect now turns his attention to the sensible stuff the world is made of. We start with a Receptacle that is capable of taking on different shapes like some sort of medium. It is also compared to a womb and space. The objective is to describe how matter arises and exists. But Plato has no word for matter. His student Aristotle will adopt the word that will ever after name the stuff of the world: hylē (originally: ‘forest, firewood, wood’), translated into Latin as materia, and rendered into English as ‘matter.’ But for Plato it remains nameless.[7]
Plato’s matter will be composed of triangles, preferably the simplest and most elegant kinds. One will be formed by cutting an equilateral triangle in two, by dividing it from the apex to the center of the opposite side. The other will be made by dividing a square into four congruent triangles. These triangles can then be reassembled into larger triangles or squares and into three-dimensional figures such as pyramids and cubes. The first set of triangles can be assembled into various shapes, while the second set can be assembled into smaller or larger cubes. This Plato’s geometry allows for fire, air, and water to be transformed into each other, and for earth to be manifested in various versions, and for the elements to interact.[8] Plato thus creates a theoretical chemistry based on basic atoms (simple solids) composed of subatomic particles (simple triangles).
The world, accordingly, is ordered into material components which are at least sometimes animated by soul, which is capable of possessing intelligence. The inchoate powers that pre-existed now become organized into objects that can react to outside forces and sometimes can act for themselves.
[1] Plato Timaeus 30a-c.
[2] Plato Timaeus 30c-31b.
[3] Plato Timaeus 31b-32c; Friendship (Philia) joins them together, apparently a legacy of Empedocles; Cornford 1937: 44 n. 4.
[4] Plato Timaeus 35a-37a.
[5] Plato Timaeus 37c-39e.
[6] Plato Timaeus 40d-45b.
[7] Plato Timaeus 52a-53b.
[8] Plato Timaeus 53b-57c.