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Primary sourceBook1687

Principia Mathematica, Page 1: Definitions

Isaac Newton · 1687

The opening page of Newton's 1687 Principia, where he lays out the definitions underlying his physics.

This is the opening page of Newton's own foundational scientific work, written in his own words.

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Title page with a page number marked [1] at top, reading PHILOSOPHIAE NATURALIS Principia MATHEMATICA, followed by the heading Definitiones and Def. I, with a Latin definition of quantity of matter in italic type. Faint bleed-through text from the reverse page is visible.
Isaac Newton, Philosophiae Naturalis Principia Mathematica, page 1, 1687. Wellcome Collection, London.

About this source

What it is

This is page one of Philosophiae Naturalis Principia Mathematica, Isaac Newton's great work of 1687. It begins with his Definitions, starting with the idea of quantity of matter, written in Latin. The book is held by the Wellcome Collection in London.

Why it matters

The Principia set out the laws of motion and universal gravitation that shaped physics for centuries. Starting with careful definitions shows how Newton built his science on precise, logical foundations rather than vague description.

Look closer

  • Why might Newton have started his book with definitions instead of experiments?
  • What does the Latin language tell you about who could read this book at the time?
  • What can you tell about the printing and age of the book from its appearance?

This book is part of the curated material that grounds the AI version of Isaac Newton on Humy.ai — when students ask about related events, the AI can quote it and cite it.

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Title page of the 1687 first edition of Newton's Principia. Large capitals read PHILOSOPHIÆ NATURALIS PRINCIPIA MATHEMATICA, with author credit, Imprimatur by S. Pepys, dated Julii 5, 1686, and London printing by Josephi Streater, Anno MDCLXXXVII.Book

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Philosophiæ Naturalis Principia Mathematica

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Isaac Newton · 1687

Engraved portrait of Sir Isaac Newton, a man with long curled wig and dark robe, bust-length, against a shaded background. Caption below reads 'SIR ISAAC NEWTON' and publisher 'William Collins Glasgow & London'.Painting

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J. Scott, after Sir Godfrey Kneller · 1702 (print made later)

Title page of the 1704 first edition of Newton's Opticks. Red and black letters read 'OPTICKS: OR, A TREATISE OF THE REFLEXIONS, REFRACTIONS, INFLEXIONS and COLOURS OF LIGHT', followed by 'Also Two Treatises of the Species and Magnitude of Curvilinear Figures'. Imprint: London, printed for Sam. Smith and Benj. Walford, MDCCIV.Book

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Opticks, or a Treatise of the Reflections, Refractions, Inflections and Colours of Light

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