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What properties did Democritus assign to atoms?
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Atomism
Epicurus, bronze bust from a Greek original, c. 280ā270 bce; in the Museo Archeologico Nazionale, Naples.
Democritus, a central figure in ancient atomism, theorized that the physical world is composed of an infinite number of atoms moving within an infinite void. He assigned the following properties to these atoms:
- Quantitative Nature: Atoms are characterized solely by quantitative properties, specifically size, shape, position, and arrangement.12
- Indivisibility and Eternity: Atoms are eternal, uncaused, and indivisibleāso small that their size cannot be further diminished.2
- Physical State: They are absolutely full, incompressible, and homogeneous, containing no pores.2
- Lack of Qualitative Differences: Atoms possess no inherent qualitative properties (such as color, taste, or temperature). Perceived qualities like "sweet," "bitter," or "hot" are merely conventional impressions caused by the specific configurations and motions of atoms impinging on the senses.2
- Motion: Motion is an eternal, inherent property of atoms, occurring as a mechanical necessity within the vacuum of the void.2
By reducing all observable phenomena to these quantitative differences, Democritus established a purely mechanical system to explain the universe.12