What Latin phrase in Newton's General Scholium means 'I frame no hypotheses'?

The Latin phrase meaning “I frame no hypotheses” in Newton’s General Scholium is “Hypotheses non fingo.” Newton used it while discussing the unknown cause of gravity in the second edition of the Principia, published in 1713.

The phrase expressed Newton’s methodological restraint: observations showed that bodies gravitate toward one another, but they did not yet establish the mechanism responsible for gravity. He argued that unsupported conjectures had no place in experimental philosophy, while propositions inferred from phenomena could be generalized by induction.

Translations vary slightly. “I frame no hypotheses” is the traditional rendering, while “I feign no hypotheses” or “I contrive no hypotheses” can also be found. The Latin verb fingo can carry meanings related to forming, fashioning, or inventing, so the wording is not perfectly fixed.

The slogan should not be taken to mean Newton never used hypotheses. His broader scientific practice involved models and conjectures; the statement specifically rejects arbitrary claims not grounded in observed phenomena.