Space and geometry in the light of physiological, psychological and physical inquiry (1906)
Mach, Ernst, 1838-1916, McCormack, Thomas Joseph, 1865-1932 · Chicago The Open court publishing company; [etc., etc.] · leaf 81
e-angled triangle having the sides a, b, and c be displaced in the direction of the side b, only a and c will, by the principle above stated,describe equivalent parallelograms, which are alikein an equal pair of parallel sides on the same paral-lels. If a make with b a right angle, and the… … Fig. 11. square. But the two parallelograms are, by the ob-servation which just precedes, equivalent respectivelyto a2 and bz,—and with this the Pythagorean the-orem is reached. The same result may also be attained (Fig. 11)by first sliding the triangle a distance a at right an-gles to a, and then…
Geometry -- Foundations · Space perception
Internet Archive · Gerstein Library, University of Toronto · Public Domain Mark 1.0. Free to use for anything.
