ALVARO-ALBERTO has published an article (An. Acad. Brasil. Ciencis, 18, No. 1, March 31, 1946) which misunderstanding regarding the teaching of Aristotle on the velocities attained by falling bodies or different masses. It is often assumed that he taught that the velocity was proportional to the weight of the body, and that Galileo was the first to show the falsity of this assumption. A letter from J. F. Hardcastle which appeared in Nature, 92, 584, January 22, 1914, pointed out that Aristotle was referring to motion in a resisting medium, and that the velocity which he was considering was the terminal velocity. This velocity is attained when the force of resistance in the medium in which the body is moving is equal to the weight of the body. Greenhill had also a letter in the same issue, and in the following week Sir William Ramsay and Sir Oliver Lodge had letters which supported the point of view of Hardcastle and Greenhill. Hardcastle quotes from St. Thomas Aquinas's “Opera Omnia” (Leonine edition), which shows quite clearly that different media were considered by Aristotle—earth, air or water or other things—and if air is twice as ‘subtile’ as water, then for an equal distance the time of translation in water will be twice that in air. It may be added that the story, so often repeated, about Galileo dropping the weights from the Leaning Tower of Pisa close to the professors' heads as they came out from their lectures is now admitted, like some other stories about Galileo, to be apocryphal. Among these must be included the story that Galileo was the first to disprove the alleged statement of Aristotle about the velocities attained by falling bodies of different weights.
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Aristotle's Views on Falling Bodies. Nature 158, 906–907 (1946). https://doi.org/10.1038/158906e0