Source: Before Galileo, The Birth of Modern Science in Medieval Europe (2012), p. 189
“Descartes maintained his confidence in the instantaneity of light. … Yet in his derivation of the law of refraction, Descartes reasoned that light travelled faster in a dense medium than in one less dense. He seems to have had no qualms about comparing infinite magnitudes!”
Source: The Rainbow: From Myth to Mathematics (1959), p. 204
Help us to complete the source, original and additional information
Carl B. Boyer 15
American mathematician 1906–1976Related quotes

Accord de différentes loix de la nature qui avoient jusqu’ici paru incompatibles (1744)

Query 20
Opticks (1704)

Accord de différentes loix de la nature qui avoient jusqu’ici paru incompatibles (1744)
Source: Mathematical Thought from Ancient to Modern Times (1972), p. 580
Context: Fermat knew that under reflection light takes the path requiring least time and, convinced that nature does indeed act simply and economically, affirmed in letters of 1657 and 1662 his Principle of Least Time, which states that light always takes the path requiring least time. He had doubted the correctness of the law of refraction of light but when he found in 1661 that he could deduce it from his Principle, he not only resolved his doubts about the law but felt all the more certain that his Principle was correct.... Huygens, who had at first objected to Fermat's Principle, showed that it does hold for the propagation of light in media with variable indices of refraction. Even Newton's first law of motion, which states that the straight line or shortest distance is the natural motion of a body, showed nature's desire to economize. These examples suggested that there might be a more general principle. The search for such a principle was undertaken by Maupertuis.

Les Loix du Mouvement et du Repos, déduites d'un Principe Métaphysique (1746)