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When was $\pi$ first suggested to be irrational?

According to Wikipedia, this was proved in the 18th century.

Who first claimed / suggested (but not necessarily proved) that $\pi$ is irrational?

I found a passage in Maimonides's Mishna commentary (written circa 1168, Eiruvin 1:5) in which he seems to claim that $\pi$ is irrational. Is this the first mention?

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    Maybe should exclude Wiki as source of information... and +1 interesting question.2012-08-01
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    @draks: Why would you exclude information just because it is found in some Wiki?2012-08-01
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    @celtschk Because it might not be reliable.2012-08-01
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    Since when does the reliability of information depend on the medium it was written on?2012-08-01
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    @celtschk I also usually trust Wikipedia. Not everyone does.2012-08-01
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    Wiki $\neq$ Wikipedia. You can make an argument against trusting Wikipedia (just as you might e.g. make an argument against some specific journal of which you don't think they do peer review the way they should), however there's no reason to mistrust all Wikis (just as there is no reason to mistrust all journals).2012-08-01
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    @celtschk Of course a wiki (lowercase) is not Wikipedia. However, I assumed draks was referring to Wikipedia.2012-08-01
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    It's not obvious to me that, e.g., Euclid and Archimedes would have considered $\pi$ to be a number in the same sense that they considered $\sqrt{2}$ to be a number. In Euclid, numbers are represented as comparisons of one segment to another, e.g., $\sqrt{2}$ would be the ratio of a square's diagonal to its edge. You can't construct segments in the ratio of $\pi$ using Euclid's postulates. Take a look at Proposition 1 here http://en.wikipedia.org/wiki/Measurement_of_a_Circle , and note how Archimedes states what we'd express as $A=\pi r^2$ without referring to $\pi$ as a number.2012-08-01
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    @celtschk I just thought, that the OP was already aware of the Wikipedia pages, that show up when I start to google it. I didn't write it like that, but it was my intention. Wiki is also one of my primary source of information, but if I had asked this question, I would something more than just Wikilinks... for example, the OP mentioned *Maimonides's Mishna commentary*, which would be an acceptable answer...2012-08-01
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    To translate Maimonides: "You should know that the ratio of a circle's diameter to its circumference is unknown and can never be found. And this lack of knowing is not due to our mathematical shortcomings, as the group called *Jahiliyyah* [likely a reference to pre-Islamic mathematicians -Fred] thinks. Rather, it is an intrinsic property of this ratio that a precise value is unknowable, and its nature is that it cannot be known, although approximations are known."2018-03-19

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