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?