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How did Dalton’s view of atoms in chemical reactions resemble Democritus’s view?

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Bronze bust of Epicurus with a full beard and draped clothing, displayed on a round inscribed base at the National Archaeological Museum of Naples. — Atomism Epicurus, bronze bust from a Greek original, c. 280–270 bce; in the Museo Archeologico Nazionale, Naples.

John Dalton’s view of atoms in chemical reactions resembled that of the ancient Greek philosopher Democritus in one fundamental respect: the preservation of atomic identity.1

Both thinkers maintained that atoms remain intrinsically unchanged throughout the process of a chemical reaction. In this view, observable changes in matter are not the result of the atoms themselves being altered, but rather the result of the separation, rearrangement, and new combinations of these immutable particles.213

While Dalton’s scientific theory differed from Democritus’s philosophical speculation in many ways—such as Dalton’s focus on measurable atomic weights and the specific ratios in which elements combine—they shared the core conviction that the fundamental building blocks of matter persist as distinct, unchanging entities during the formation of compounds.31