Methodology
How we decide what goes on this site — and how we mark what we don't know.
What this site is
A neutral reference guide to Isaac Newton (1642–1727): his life, his writings, the people around him, and how his reputation was made and remade afterward. It is written for curious readers, students, and educators — not as biography-as-worship and not as debunking-as-sport.
Dates: the Julian calendar problem
England used the Julian calendar throughout Newton’s lifetime (the Gregorian reform reached England only in 1752, twenty-five years after his death). This creates two wrinkles:
- Old Style / New Style year dating. Before 1752, the English legal year began on 25 March, so a date like “5 February 1675” in a contemporary English letter falls in what we now call February 1676. On this site, dates are given in the form contemporaries used (Old Style), with the modern (New Style) equivalent noted where the difference matters.
- The 10–11 day shift. The Julian calendar ran 10 days behind the Gregorian in the 1600s and 11 days behind in the 1700s. So Newton’s birth — 25 December 1642 in England — was 4 January 1643 by the calendar most of Europe already used.
We state which convention we are using whenever a date could confuse.
Quotations: three tiers
Newton is one of the most misquoted figures in science. Every quotation on this site carries its tier:
- Documented — traceable to Newton’s own published or manuscript writing, with the work named (e.g., Principia, the Opticks, his correspondence as edited by Turnbull).
- Reported — attributed by a contemporary or near-contemporary source (a memoir, a biographer’s anecdote). These appear only with the reporter named and the chain of transmission stated.
- Unverified — famous lines that cannot be traced to Newton at all. These are not quoted as his words anywhere on this site; the sayings page lists the worst offenders so readers can stop repeating them.
We never present paraphrase as quotation, and we give original spellings where they matter (e.g., “ye sholders of Giants”).
Uncertainty is explicit
Where scholars disagree — the meaning of the “shoulders of giants” line, the cause of Newton’s 1693 breakdown, how much his alchemy fed his physics — we say so, name the positions, and do not pick a winner the evidence can’t support. A claim without a named source is treated as unknown, not as fact.
People and context
Historical figures are described as they are documented, including the unflattering parts (Newton’s vindictiveness in the calculus dispute, his ruthlessness as a Mint prosecutor). Context is kept proportional: this is a Newton reference, not a general history of 17th-century England, so background appears only where it explains him.
Images: the honesty rule
Historical subjects get real pictures only — period portraits, title pages, buildings, manuscripts — drawn from public-domain or openly licensed collections (primarily Wikimedia Commons), each with a provenance record in the image credits on this page. We never use AI-generated imagery to fake history or a real person’s face. Generated imagery appears only for the stream’s dramatization character, and is always labeled as dramatization art.
Sources
Primary sources come first: Newton’s own writings, his correspondence, and the archives that hold them (see sources). Secondary claims are checked against modern scholarship — notably the Newton Project’s editions — before they are stated as fact.
Source notes
- Calendar conventions follow the standard scholarly practice described in the Newton Project editorial materials.
- Quote-tier policy is this site’s own editorial standard (2026-09-26); it is stricter than most popular Newton writing, deliberately.
- Image policy: real images for historical subjects; AI-generated imagery only for abstract or dramatization art, labeled as such (see the image credits on this page).