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Well, all of us know the real numbers.

-1000<-122.34<-\pi^e<-\gamma<-0.00000001<-0.0000000000000000001 \in \mathbb{R}

But if we continue this way, looks like the largest negative number will be

$-0.0000\dots1$, but this number, as defined by Cantor, is $0$.

So can we say the largest negative number is $0$?

If not, why not?

Edit:

I agree $0$ is not a negative number. How about the question, what's the largest negative number?

Is there no answer to this question? If the answer is that there is no largest negative number, how can we prove this mathematically?

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    @ GaroDan. In the same vein : What is the largest real number smaller than 2016 ? -2015-12-26

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In the real numbers (or the rationals) there is no "largest negative number", much like there is no "smallest positive number".

The order of the real numbers is dense, if we define the negative numbers as \{x\in\mathbb R\mid x<0\} then between every $x$ in that set and $0$ there is another number, so if $x$ is a negative number there is some $y$ which is negative and is slightly larger than $x$. For example, $y=\frac{x}2$.

We have a philosophical conundrum on our hands as well, why should every partial order attain a maximal element? (Indeed, there is no reason!)

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    Thx Asaf, I think this ends the enquire.^^2012-04-13