Hypotheses (Non) Fingo

Toni Vogel Carey considers Sir Isaac Newton’s most (in)famous remark.

For two centuries and more, Isaac Newton (1642-1727) was the very god of science, and commentators still hang on his every word, especially his most famous dictum, hypotheses non fingo. Besides, this saying makes for some intriguing, if not very flattering, stories about Newton himself.

The relevant passage occurs in the final General Scholium of Newton’s Principia (1687). (The book’s full title is Philosophiae Naturalis Principia Mathematica, or The Mathematical Principles of Natural Philosophy). Here is the original English translation of 1729 by Francis Motte, which is still in use:

“Hitherto we have explained the phenomena of the heavens and of our sea by the power of gravity, but have not yet assigned the cause of this power … I have not been able to discover the cause of those properties of gravity from phenomena, and I frame no hypotheses [hypotheses non fingo]; for whatever is not deduced from the phenomena is to be called an hypothesis; and hypotheses, whether metaphysical or physical, whether of occult qualities or mechanical, have no place in experimental philosophy … To us it is enough that gravity does really exist, and acts according to the laws which we have explained, and abundantly serves to account for all the motions of the celestial bodies, and of our sea.

This article is available to subscribers only.

If you are a subscriber please Log In to your account.

To buy or renew a subscription please visit the Shop.

If you are a subscriber you can contact us to create an account.


This site uses cookies to recognize users and allow us to analyse site usage. By continuing to browse the site with cookies enabled in your browser, you consent to the use of cookies in accordance with our privacy policy.