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Single Idea 15866

[from 'Principia Mathematica' by Isaac Newton, in 27. Natural Reality / A. Classical Physics / 1. Mechanics / a. Explaining movement ]

Full Idea

Following Kepler, Newton assumed a law of universal gravitation, thus reclassifying free fall as a violent motion and, with his First Law, fixing horizontal motion in the absence of constraints as natural

Gist of Idea

Newton reclassified vertical motion as violent, and unconstrained horizontal motion as natural

Source

report of Isaac Newton (Principia Mathematica [1687]) by Rom Harré - Laws of Nature 1

Book Reference

Harré,Rom: 'Laws of Nature' [Duckworth 1993], p.26


A Reaction

This is in opposition to the Aristotelian view, where the downward motion of physical objects is their natural motion.