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There is no greater real number.

There is no positive integer that is greater than any other positive integer.

I was wondering if the negative sign is necessary here or not. Are there many different ways of writing the two statements?

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    You can write these by using that $$\neg \exists x (P(x)) = \forall x (\neg P(x)).$$2012-10-30
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    The *literal* translation of the mathematical English into symbols would use negation. For the first problem, we can say it using the equivalent "for any real number $x$, there is a real number $y$ such that $x \lt y$." However, negation cannot *always* be dispensed with.2012-10-30
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    @AndréNicolas ... especially not in the statement "negation cannot always be dispensed with" :)2012-10-30
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    I don't understand why you can write y > x, because it could also be interpreted as there is a greater real number y.2012-10-30

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