How Was the Pythagorean Thoerem Proved?
Date: 06/05/2006 at 12:09:12 From: Phyllis Subject: Pythagorean Theorem How did Pythagoras derive the Pythagorean Theorem?
Date: 06/05/2006 at 14:53:13 From: Doctor Peterson Subject: Re: Pythagorean Theorem Hi, Phyllis. According to my books, we know so little about Pythagoras that the best we can say is that "the Pythagorean theorem is ascribed to the Pythagoreans" (him and his followers); we don't know how, or even whether, he or they actually proved it. They were not the first to know it, though; the Chinese, the Babylonians, and perhaps the Egyptians, also were aware of it. Here is a quotation from D. E. Smith's History of Mathematics: The proof of the proposition is attributed to Pythagoras (c. 540 B.C.) by various writers, including Proclus (c. 460), Plutarch (1st century), Cicero (c. 50 B.C.), Diogenes Laertius (2nd century), and Athenaeus (c. 300). No one of these lived within, say, five centuries of Pythagoras, so that we have only a weak tradition on which to rest the general belief that Pythagoras was the first to prove the theorem. It would seem as if such an important piece of history would have some mention in the works of a man like Aristotle; but, on the other hand, it is difficult to see how such a tradition should be so generally received unless it were well founded. Not only are we not positive that the proof is due to Pythagoras at all, but we are still more in doubt as to the line of demonstration that he may have followed. You can see Euclid's proof in the Elements; but there's a good chance that that is not what Pythagoras would have done! If you have any further questions, feel free to write back. - Doctor Peterson, The Math Forum http://mathforum.org/dr.math/
Search the Dr. Math Library:
Ask Dr. MathTM
© 1994-2015 The Math Forum