DESMOND: Sorry?

DAN: Why would I put you through the headache of time travel, you know? You know what I mean, it just seems a little... unnecessary. And don't you think that my esteemed colleagues could [bad word] up with something just a little more believable, huh? Wha—what kind of a prank is that? Huh, paradox. So uninspired. 

.****.

DAN: This is where I do the things Oxford frowns upon. Alright, this, this future version of me... uh, he referenced this meeting, right? Obviously, so, so I would remember [bad word] to Oxford, right? I would remember this, here, right now. 

***
 I think Eloise's brain short-circuited. The jumps between the present and the future...she eventually, she couldn't tell which was which — she had no anchor.

DESMOND: Wh...what do you mean, anchor?

DAN: Something familiar in both times. All this, see this is all variables, it's random, it's chaotic. Every equation needs stability, something known. It's called a constant. Desmond, you have no constant. When you go to the future, nothing there is familiar. So if you want to stop this, then you need to find something there...something that you really, really care about...that also exists back here, in 1996.