Full Idea
The soul is a body made up of fine parts distributed throught the entire aggregate, most closely resembling breath with a certain admixture of heat, in one way resembling breath and in another resembling heat
Clarification
The 'aggregate' is a combination of atoms
Gist of Idea
The soul is fine parts distributed through the body, resembling hot breath
Source
Epicurus (Letter to Herodotus [c.293 BCE], 63)
Book Reference
Epicurus: 'The Epicurus Reader', ed/tr. Inwood,B. /Gerson,L. [Hackett 1994], p.13
A Reaction
Remember that 'psuché' refers as much to the life within a creature as it does to the consciousness. The stoics seem to have held a similar view.