atomism

Noun

• (chemistry) any theory in which all matter is composed of tiny discrete finite indivisible indestructible particles
  • the ancient Greek philosophers Democritus and Epicurus held atomic theories of the universe
    

• (psychology) a theory that reduces all mental phenomena to simple elements (sensations and feelings) that form complex ideas by association

Related words

• Synonyms: 
  atomic theory , atomist theory , atomistic theory
• Antonyms: 
  holism , holistic theory