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### Course: Math for fun and glory>Unit 1

Lesson 9: Other cool stuff

# What was up with Pythagoras?

Pythagoras had a problem with beans and irrationality. What really happened? I don't know! The square root of two is irrational, and beans are delicious. Created by Vi Hart.

## Want to join the conversation?

• Did Pythagoras really invent the Pythagorean theorem?
• There is some conjecture that followers of Plato may have constructed the myth of Pythagoras discovering the formula 2 centuries after his death. It appears that the earliest mention of Pythagoras as the author is 4th Century AD. The section in the Wikipedia article concludes with the following (without citations):
“Because of the secretive nature of his school and the custom of its students to attribute everything to their teacher, there is no evidence that Pythagoras himself worked on or proved this theorem. For that matter, there is no evidence that he worked on any mathematical or meta-mathematical problems.”

Shocking! I thank you very much for this question. It has inspired me to look into this further. I will let you know if I find out anything more. Does anyone else know of any reliable sources for us on this subject?
• At , why does it have to be even?
• the leg must be even because it is divisible by two twice, not just once
• Coming from Mexico, I love beans (yeah, its true, so what) but I also know that the kind of beans showed in the drawings (Phaseolus vulgaris) are originally from America and Pythagoras didn't knew them (unless he did discovered America, which would be cool). So, my question is what kind of beans was He afraid of (and whether those kind of beans would be the study subject of Flatology as well)?
• I found an article that may provide some information on "Pythy's view of the bean" See: Title: Pythagoras and the bean. By: Williams, Kate Garnons, Contemporary Review, 00107565, Oct93, Vol. 263, Issue 1533 p209. 3p - If you are unable to find the article online, you may be able to have your local library email you a copy.
(1 vote)
• Why does she say b.c.e. if she wrote Jesus on the time line
• I still consider that odd, since, BCE stands for Before Common Era, and was invented to get God out of the picture, since BC means Before Christ. I don't care about PC... I will shamelessly say and write BC and AD.
• I think the way he died was he ran into the bean field, thinking that his pursuers were afraid of beans. But when he threw them at them, they only laughed and slaughtered him. What do you think?
• No, no, no. Neither of you are correct. He fought back with a bean stalk because he thought beans were good weapons but him (and his weapon) got slashed in half and his guts were sacrificed to Apollo.
• Why does Vi Heart talk so fast? Does she speed it up?
• She speeds up the video, and she probably speeds up her voice too to match it.
(1 vote)
• does anyone know any other whole nunber thing that works other than 3,4,5?
• You're looking for 'Pythagorean triples'. Three whole number sides that give you a right triangle, like 3,4,5 or 5,12,13 or 8,15,17.

There are infinitely many. One easy way to generate them is to square any odd number (say 7 which gives you 49) and then the two consecutive numbers that add up to 49 (24 and 25 in this case) give you the other two sides. So, 7,24,25 is also a right triangle.
• Did the Greeks use Roman Numerals?
• No. They used the letters of their own alphabet to write numbers. Alpha was one, veeta was two, gamma was three, and so on up to theeta, which was nine (the obsolete digamma was six). Yota was ten, kappa was twenty, and so on up to pi, which was eighty. The obsolete koppa was ninety. Roh was 100, sigma was 200, and so on up to omega, which was 800, and the obsolete sampi was 900. For one to nine thousand, alpha through theeta was used with the mark ͵ to the left of the letter. Ten thousand was one followed by an uppercase mi, a hundred million had two uppercase "mi"s, and so on. (To distinguish these numbers from words, they were either overlined or had the mark ʹ after them.)
(1 vote)
• Does anyone have any idea why Pythagoras was afraid of beans? Like seriously, according to this, he died because of his fright of beans.