jan 1, 450 BC - Four elements
Empedocles (of Acagras in Sicily, c. 492- 432 BC) was a philosopher and poet. The foundations of Empedocles' physics lie in the assumption that there are four 'elements’ of matter, or ‘roots’ as he called them: earth, air, fire and water. These elements were able to create all things, including all living creatures, by being 'mixed' in different combinations and proportions. Each of the elements however, retained its own characteristics in the mixture, and each was eternal and unchanging.
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