Overview
Thumos (also commonly spelled 'thymos'; ) is the Ancient Greek concept of "spiritedness" (as in "a spirited stallion" or "spirited debate"). The word indicates a physical association with breath or blood and is also used to express the human desire for recognition. It is not a somatic feeling, as nausea and giddiness are.
History
Homer
In Homer's works, thumos was used to denote emotions, desire, or an internal urge. Thumos was a permanent possession of living man, to which his thinking and feeling belonged. When a Homeric hero is under emotional stress, he may externalize his thumos and converse with or scold it. Achilles, in the Iliad, cares for his own honour; he keeps gods and deities in his heart; "...the thunderous lord of Hera might grant you the winning of glory, you must not set your mind on fighting the Trojans, whose delight is in battle, without me. So you will diminish my honour (thumos)."
Democritus
Democritus used "euthymia" (i.e. "good thumos") to refer to a condition in which the soul lives calmly and steadily, being disturbed by no fear, superstition, or other passions. For Democritus euthymia was one of the root aspects of the goal of human life.
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