You accompany the man as he joins his fellow workers in the grove. They're relaxing on the grass, drinking beer and chatting. As you sit down, one of the men passes you a bottle. You thank him and try to catch up on the conversation, but you can tell that the speakers have had a fair bit to drink...
: ...you can definitely travel in time. What's wrong with that?? When we dream we are transported to all sorts of bizarre worlds. When I think about Pluto, I am immediately grasping something a million miles away. Our minds are not trapped.
: Yeah, but in both those examples our bodies are still here, in the now! A dream is just some confused images in your head. When you think about Pluto it is even less impressive, because you are simultaneously aware that you are not actually on Pluto. I can just kick you and tear your attention right back to the here and now.
: Okay forget the examples. What do you even mean by "here and now"? By the time you formulate some awareness of "now", you are just referring to some memory from a few moments prior. All your logic is behind you, you can never grasp the present. Who even knows if the memories are legitimate.
Also, what difference does it make if my body is here now? Now is a relative term, my body is no more here than it is anywhere else that it inhabits; we are smeared across time. In an absolute sense I am five minutes ago, and I am five minutes from now - no point is privileged and you can never grasp a moment.
: Who gives a toss, how is any of that going to magically transport you back to ancient antiquity, or some future colony on Mars?
: Well, who am I for purposes of this question, other than my awareness? And look how easy it is to launch my awareness to some distant place, both spatially and chronologically.
But fine, time travel is necessarily impossible if you expect it to involve placing my current self into a context where my current self "is not". We're not going to change anything in some absolute sense like that, obviously; the parts of the chronology where I am not present will remain pristine. However, to the extent that I am present in places near those points, I will be aware of it in the fullness of time.
: Next you'll tell me that you when you die your awareness will be reincarnated in some ancient or future body. It's all nonsense, you can't time travel, you are never going to visit the real deal antiquity in person.
: If you want to push it, you don't know that, strictly speaking. You don't know if I was in ancient antiquity; maybe I will time travel and achieve great things, maybe there is a road that leads to that world. When I get there, I will adopt a pseudonym and be recorded in history under that name.
: If you walk down that road tomorrow, it's a future act, so how is the road supposed to lead to antiquity, and in turn allow you to impact whatever I'm reading in a history book today?
: Well, our awareness seems to travel along a particular chronological path, in a particular direction. However, do we know this to be the only possibility, or is that just something we learnt via induction during our brief lives here?
Maybe I discover a different path, or a way of travelling in a different direction, and so I will slip through at some unseen angle and wander into my past. I won't change anything, for I will always have been there, necessarily. Just like I am at all other points I have visited.
Actually, you might be a big fan of my work as an ancient philosopher. Maybe we should go through your bookshelf. Maybe we'll find a book that reads like something I would have written.
: You are so full of shit.
: Probably, but it sounds good so I believe it. Maybe I'll take you with me when I figure it all out.
The men laugh and finish their drinks. Judging by the number of bottles next to them, it has been a long conversation and they are unlikely to remember all the details tomorrow. Your friend also finishes his drink, before making some recommendations:
If you're inclined to go back to the temple before the exhibits close for the day, I'd recommend checking in on the new professor. He's working on something special, or so I hear. At the very least it will be a lot more informative than drunken debates in the grove, but on the other hand there's no drinking allowed there.
You could also go back to that guy in the entrance hall giving the monologue, or at least check out his brother's exhibit on Distinction. Or just retire to the Guesthouse. For my part, I need to get some rest and prepare for tomorrow. This place isn't going to build itself.