Timaeus(Greek: Timaios) is a theoretical treatise of Plato in the form of a Socratic dialogue, written circa 360 BC. The work puts forward speculation on the nature of the physical world. It is followed by the dialogue Critias.
Speakers of the dialogue are Socrates, Timaeus of Locri, Hermocrates, Critias. Some scholars have argued that it is not the Critias of the Thirty Tyrants who is appearing in this dialogue, but his grandfather, who is also named Critias.
The dialogue takes place the day after Socrates described his ideal state. In Plato's works such a discussion occurs in the Republic. Socrates feels that his description of the ideal state wasn't sufficient for the purposes of entertainment and that \"I would be glad to hear some account of it engaging in transactions with other states\".
Hermocrates wishes to oblige Socrates and mentions that Critias knows just the account to do so. Critias proceeds to tell the story of Atlantis, and how Athens used to be an ideal state that subsequently waged war against Atlantis. Critias believes that he is getting ahead of himself, and mentions that Timaeus will tell part of the account from the origin of the universe to man. The history of Atlantis is postponed to Critias. The main content of the dialogue, the exposition by Timaeus, follows.Synopsis of Timaeus' accountNature of the Physical World
Timaeus begins with a distinction between the physical world, and the eternal world. The physical one is the world which changes and perishes: therefore it is the object of opinion and unreasoned sensation. The eternal one never changes: therefore it is apprehended by reason.
The speeches about the two worlds are conditioned by the different nature of their objects. Indeed, \"a description of what is changeless, fixed and clearly intelligible will be changeless and fixed,\", while a description of what changes and is likely, will also change and be just likely. \"As being is to becoming, so is truth to belief\". Therefore, in a description of the physical world, one \"should not look for anything more than a likely story\".
Timaeus suggests that since nothing \"becomes or changes\" without cause, then the cause of the universe must be a demiurge or God, a figure Timaeus refers to as the father of the universe. And since the universe is fair, the demiurge must have looked to the eternal model to make it, and not to the perishable one. Hence, using the eternal and perfect world of \"forms\" or ideals as a template, he set about creating our world, which formerly only existed in a state of disorder.Purpose of the Universe
Timaeus continues with an explanation of the creation of the universe, which he ascribes to the handiwork of a divine Craftsman. The demiurge, being good, wanted there to be as much good as was the world. The demiurge is said to bring order out of substance by imitating an unchanging and eternal model (paradigm). The ananke was the only other co-existent element or presence in Plato's cosmogony. Later Platonists clarified that the eternal model existed in the mind of the Demiurge.
(Later in history the term \"demiurge\" became a term of vilification by Gnostics who purported that the demiurge was a fallen and ignorant god creating a flawed universe, but this was not how Plato was using the term.)Properties of the Universe
Timaeus describes the substance as a lack of homogeneity or balance, in which the four elements (earth, air, fire and water—see Platonic solids) were shapeless, mixed and in constant motion. Considering that order is favourable over disorder, the essential act of the creator was to bring order and clarity to this substance. Therefore, all the properties of the world are to be explained by the demiurge's choice of what is fair and good; or, the idea of a dichotomy between good and evil.
First of all, the world is a living creature. Since the unintelligent creatures are in their appearance less fair than intelligent creatures, and since intelligence needs to be settled in a soul, the demiurge \"put intelligence in soul, and soul in body\" in order to make a living and intelligent whole. \"Wherefore, using the language of probability, we may say that the world became a living creature truly endowed with soul and intelligence by the providence of God\".
Then, since the part is imperfect compared to the whole, the world had to be one and only. Therefore, the demiurge did not create several worlds, but one and unique world.
The creator decided also to make the perceptible body of the universe by four elements, in order to render it proportioned. Indeed, in addition to fire and earth, which make bodies visible and solid, a third element was required as a mean: \"two things cannot be rightly put together without a third; there must be some bond of union between them\". Moreover, since the world is not a surface but a solid, a fourth mean was needed to reach harmony: therefore, the creator placed water and air between fire and earth. \"And for these reasons, and out of such elements which are in number four, the body of the world was created, and it was harmonised by proportion\".
As for the figure, the demiurge created the world in the geometric form of a globe. Indeed, the round figure is the most perfect one, because it comprehends or averages all the other figures and it is the most omnimorphic of all figures: \"he [the demiurge] considered that the like is infinitely fairer than the unlike\".
The creator assigned then to the world a rotatory or circular movement, which is the \"most appropriate to mind and intelligence\" on account of its being the most uniform.
Finally, he created the soul of the world, placed that soul in the center of the world's body and diffused it in every direction. Having thus been created as a perfect, self-sufficient and intelligent being, the world is a god .The Creation of the World Soul
Timaeus then explains how the soul of the world was created (Plato's following discussion is obscure, and almost certainly intended to be read in light of the Sophist). The Demiurge combined three elements: two varieties of Sameness (one indivisible and another divisible), two varieties of Difference (again, one indivisible and another divisible), and two types of Being (or Existence, once more, one indivisible and another divisible). From this emerged three compound substances, intermediate (or mixed) Being, intermediate Sameness, and intermediate Difference. From this compound one final substance resulted, the World Soul. He then divided following precise mathematical proportions, cutting the compound lengthways, fixed the resulting two bands in their middle, like in the letter Χ (chi), and connected them at their ends, to have two crossing circles. The Demiurge imparted on them a circular movement on their axis: the outer circle was assigned Sameness and turned horizontally to the right, while the inner circle was assigned to Difference and turned diagonally and to the left.
The demiurge gave the primacy to the motion of Sameness and left it undivided; but he divided the motion of Difference in six parts, to have seven unequal circles. He prescribed these circles to move in opposite directions, three of them with equal speeds, the others with unequal speeds, but always in proportion. These circles are the orbits of the heavenly bodies: the three moving at equal speeds are the Sun, Venus and Mercury, while the four moving at unequal speeds are the Moon, Mars, Jupiter and Saturn.
Then, the demiurge connected the body and the soul of the universe: he diffused the soul from the center of the body to its extremities in every direction, allowing the invisible soul to envelop the visible body. The soul began to rotate and this was the beginning of its eternal and rational life.
Therefore, having been composed by Sameness, Difference and Existence (their mean), and formed in right proportions, the soul declares the sameness or difference of every object it meets: when it is a sensible object, the inner circle of the Diverse transmit its movement to the soul, where opinions arise, but when it is an intellectual object, the circle of the Same turns perfectly round and true knowledge arises.The Elements
Plato assumes that the minute particle of each element had a special geometric shape: tetrahedron (fire), octahedron (air), icosahedron (water), and cube (earth).
The Timaeus conjectures on the composition of the four elements which the ancient Greeks thought made up the universe: earth, water, air, and fire. Plato conjectured each of these elements to be made up of a certain Platonic solid: the element of earth would be a cube, of air an octahedron, of water an icosahedron, and of fire a tetrahedron. Each of these perfect polyhedra would be in turn composed of triangles. Only certain triangular shapes would be allowed, such as the 30-60-90 and the 45-45-90 triangles. Each element could be broken down into its component triangles, which could then be put back together to form the other elements. Thus, the elements would be interconvertible, so this idea was a precursor to alchemy.
Further, Plato posits the existence of a fifth element (corresponding to the fifth remaining Platonic solid, the dodecahedron) called quintessence, of which the cosmos itself is made. Timaeus also discusses music theory: e.g. construction of the Pythagorean scale. The last part of the dialogue addresses the creation of humans, including the soul, anatomy, perception, and transmigration of the soul.Golden Ratio
\"For whenever in any three numbers, whether cube or square, there is a mean, which is to the last term what the first term is to it; and again, when the mean is to the first term as the last term is to the mean—then the mean becoming first and last, and the first and last both becoming means, they will all of them of necessity come to be the same, and having become the same with one another will be all one\"; thereby he implies the aesthetically perfect proportion known as Golden ratio or Golden mean.Later influence
Medieval manuscript of Calcidius' Latin Timaeus translation. The Timaeus was translated into Latin by Cicero and again by Calcidius. The version by Calcidius was one of the few works of classical natural philosophy, and the only Platonic dialogue, available to Latin readers in the early Middle Ages. Thus it had a strong influence on medieval Neoplatonic cosmology and was commented particularly by 12th century Christian philosophers of the Chartres School, such as Thierry of Chartres and William of Conches, who interpreting it in the light of the Christian faith understood the dialogue to refer to a creatio ex nihilo.