κάθαρσις

Catharsis comes from Greek κάθαρσις (katharsis), meaning cleansing, purification, or purgation, from the verb kathairein (to cleanse, to purify), from katharos (pure, clean). In ancient Greek medicine, katharsis referred to the physical purging of the body — the evacuation of harmful substances through vomiting, bleeding, or other means. The body was dirty; catharsis made it clean.

Aristotle transformed the word in his Poetics (c. 335 BCE). Tragedy, he argued, achieves the catharsis of pity and fear in the audience — a purging of dangerous emotions through the safe container of art. Watching Oedipus blind himself or Medea murder her children allowed Athenians to experience extreme emotions without the extreme consequences. The theater was emotional hygiene.

The precise meaning of Aristotle's catharsis has been debated for two thousand years. Does it mean purgation (draining away harmful emotions), purification (refining emotions into something nobler), or clarification (intellectual understanding of emotion)? Scholars have argued all three. The word's ambiguity has made it one of the most productive concepts in Western thought.

Sigmund Freud and Josef Breuer adopted catharsis as a therapeutic concept in the 1890s — the 'cathartic method' of curing hysteria by bringing repressed emotions to conscious expression. Psychotherapy, in this sense, is Aristotelian theater for one. The patient is both actor and audience, and the cure is the performance of suffering.