Thales hypothesis that everything consists of water resembles modern scientific theories.

Evidence

The statement that everything is made of water is to be regarded as a scientific hypothesis, and by no means a foolish one. Twenty years ago, the received view was that everything is made of hydrogen, which is two thirds of water. … The Greeks were rash in their hypotheses, but the Milesian school, at least, was prepared to test them empirically. — Bertrand Russell, History of Western Philosophy, 161

Categorization

• XREF: XREF connects to modern particle physics theories about universal matter.
• corroborated: 2 independent passages support this claim — Bertrand Russell, History of Western Philosophy, 161