431 BC

Decades: 480s BC 470s BC 460s BC 450s BC 440s BC - 430s BC - 420s BC 410s BC 400s BC 390s BC 380s BC

Years: 436 BC 435 BC 434 BC 433 BC 432 BC - 431 BC - 430 BC 429 BC 428 BC 427 BC 426 BC
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Events

• Beginning of the Peloponnesian War
• The Greek physician and philosopher Empedocles articulates the notion that the human body has four humors- blood, bile, black bile, and phlegm, a belief which dominates medical thinking for centuries.
  

  Births

• Deaths

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