Considering a predicate Q(y,x) stating that x is greater than y, what is the difference between.
$\forall x \exists y$ $Q(y, x)$
and
$\exists y \forall x$ $Q(y, x)$
Thanks,
Considering a predicate Q(y,x) stating that x is greater than y, what is the difference between.
$\forall x \exists y$ $Q(y, x)$
and
$\exists y \forall x$ $Q(y, x)$
Thanks,
The first statement says that for every number there is a greater number (true: for any $x$, you can always pick $x + 1$ as a greater number)
The second statement says that there is a number greater than all numbers, which is clearly false! (in fact, 'all numbers' would include itself, so besides $y$ being greater than all other number (which is already false, since there is no greatest number), $y$ would also have to be greater than itself!)