The soul is a kind of « heteroclite beast », like the Chimera or Cerberus, says Plato. He represents her as an assemblage of several monsters, whose heads form a « crown ». Some of these heads are peaceful, the others are fierce and ferocious. This beastly crown thrones over the body of a lion, coupled with that of a man. All this is wrapped in human skin, which gives the observer the impression that this composite creature has the appearance of a man.ⁱ

The idea of mixing the bestial and the human in several degrees of composition is taken up in another text, Timaeus, where Plato defines the soul of the world.

The soul of the world is described as an « indivisible reality that always remains identical », a « reality that is divisible and subject to becoming « , and finally a « third form of reality », called « intermediate », which is obtained by mixing the first two kinds of realities.

The soul of the world is thus a mixture of three elements: an indivisible one, a divisible one and a third one which is itself a mixture of the first two.

It may seem a little redundant, like a mixture of a mixture with itself… Or, logically, this could also imply that the third form of reality does not mix with the first two realities, indivisible and divisible, in the same way and with the same effects, as we observe when we mix the first two kinds of realities. In short, mixing is not a linear operation, but rather an « epigenetic » one, we would say today.

God, Plato continues, took these three kinds of reality and mixed them together to melt them into a single substance.

But, how to mix the divisible with the indivisible, the « Same » with the « Other »? « The nature of the Other was rebellious to the mixture; to unite it harmoniously to the Same,[God] used constraint; then in the mixture he introduced Reality; of the three terms, he made a unity. »ⁱⁱ

The soul of the world is therefore a mixture of three terms: the Same, the Other and « Intermediate Reality ».

If we compare this mixture with the mixture of the human soul, what do we see? The human soul is composed, as we remember, of a crown of animal heads, a leonine form and a human form.

Can the terms of these two mixtures be reconciled?

The « crown of animal heads » could be analogous to the Intermediate Reality. The « lion » could be assimilated to the Same, and « man » to the Other.

We can imagine other correspondences between the structure of the soul of the world and the structure of the human soul. But the important point is elsewhere.

The fundamental idea is that the human soul is, by the very principle of its composition, the image of all things. It contains in power the possible developments of all living beings.

Plato reinforces this idea with another image. The soul comes, he says, from a « cup » where God has cast all the seeds of the universe, and « mixed them ». It follows that every soul contains in power all these seeds, all these germs, all these possibilities.

iPlato The RepublicIX, 558e

iiPlato. Timaeus, 35a,b