Absence of ACES before the FLOP

I must be slow... I don't see the difference. The wording is as show in SS. "The probaility that no player has an Ace (including yourself) "If you have no Ace the probability that no one has an Ace"

In both cases, the hole cards have been dealt and I have no Aces. There is not an ASSUMPTION indicated. Both columes state I don't have an Ace. Why would the proability of an Ace having been dealt to anyone change just because I know I don't have one?

Tell me again the difference.