Date: c. 501 B.C.

"[He used to say that] there is a greater need to extinguish hybris than there is a blazing fire."

— Heraklitus (fl. 504-1 BCE)

Date: 380-360 B.C.

"The rest of your statement, Socrates, he said, seems excellent to me, but what you said about the soul leaves the average person with grave misgivings that when it is released from the body it may no longer exist anywhere, but may be dispersed and destroyed on the very day that the man himself d...

— Plato (427 BC - 347 BC)

Date: w. 350 B.C.

"This is what led Democritus to say that soul is a sort of fire or hot substance; his 'forms' or atoms are infinite in number; those which are spherical he calls fire and soul, and compares them to the motes in the air which we see in shafts of light coming through windows."

— Aristotle (384-322 B.C.)

Date: 170

"The heart is, as it were, the hearthstone and source of the innate heat by which the animal is governed."

— Galen (129-200)