"For when a ship is floating calmly along, the sailors see its motion mirrored in everything outside, while on the other hand they suppose that they are stationary, together with everything on board."
— Nicolaus Copernicus
For When A Ship Is Floating
For when a ship is floating calmly along, the sailors see its motion mirrored in everything outside, while on the other hand they suppose that they are stationary, together with everything on board.
About this quote
Nicolaus Copernicus used this analogy in Book I, Chapter 5 of De revolutionibus orbium coelestium (1543) to argue that the apparent daily motion of the Sun and stars could be explained by the Earth's rotation rather than by the entire heavens revolving around a stationary Earth. The ship analogy — that observers in motion perceive themselves as stationary and their surroundings as moving — was one of his key arguments for the plausibility of a moving Earth.
Source
De revolutionibus orbium coelestium, Book I, Chapter 5, 1543
