The hypothesis of Leucippus, Democritus, and Epicurus, that the world is composed of a congeries of atoms, or particles of matter so minute as to be incapable of further diminution.
Of course it is quite impossible even to think of a portion of matter which has not an upper and under side, with some breadth and thickness.
“According to Democritus, the expounder of the Atomic Theory of matter, images composed of the finest atoms floated from the object to the mind.” —McCosh: Psychological Cognitive Powers , p. 23.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894
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