

Infinity is Not a number - marvin
http://scienceblogs.com/goodmath/2008/10/infinity_is_not_a_number.php

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lacker
People used to think 0 wasn't a number. Then that the square root of 2 wasn't
a number. Then that -1 wasn't a number. Then that 'i' wasn't a number.

There just isn't one official list of "what is a number". Real mathematicians
will consider anything a number temporarily if it's convenient for them.

For anyone who cares, I recommend David Foster Wallace's book "Everything and
More" for a great history of mathematicians' thoughts about infinity.

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ram1024
it's used as a number to simplify conversations. instead of saying the limit
of the expression 1/x as it tends to zero is infinity, we simplify that
statement and say 1/0 = inf. it's nothing to get mad and write a scathing
dissertation over. if you want to delve into it you can if necessary.

there are infinite stars in the heavens. decidedly untrue if you actually were
able to make a count of them. but by the limits of our ability, it is
understandably true.

it's about context i think

~~~
eru
Of course you can always use Conway's surreal numbers
(<http://en.wikipedia.org/wiki/Surreal_number>).

I can only recommend reading his book 'On Numbers and Games':

"On Numbers and Games is a mathematics book by John Horton Conway. The book is
a serious mathematics book, written by a preeminent mathematician, and is
directed at other mathematicians. The material is, however, developed in a
most playful and unpretentious manner and many chapters are accessible to non-
mathematicians." (<http://en.wikipedia.org/wiki/On_Numbers_and_Games>)

