Brian Clegg’s entertaining pop-physics book Build Your Own Time Machine: The Real Science of Time Travel (2011) has a couple of amusing examples of how grammar gets wonky when you’re talking about time travel. The first example comes in a discussion of what’s called the block universe model, which encompasses “all of space and all time that will ever be”:
If the block universe is the correct picture, even if we managed to travel backward in time, we could never do anything that would change the future, at least within a particular quantum version of the universe. Because the future and the past already exist in the block, any action we take must already exist. (We have trouble with tenses emerging from time travel here. It might be more accurate to say that any action must will have existed.)
Later, Clegg talks about “Destination Day” in Perth, when a time and place were announced to welcome possible visitors from the future. (Similar events have taken place in MIT and Baltimore.) Note that the DD website is no longer directly accessible and can be reached only in cached form via tools like the Wayback Machine – the internet equivalent of time travel. Clegg:
I can’t find any official description of what happened that day in Perth, but I suspect there was some form of welcoming committee, eagerly anticipating visitors from the future to pop into existence. Of course now March 31, 2005, is in the past, and we aren’t so much awaiting them as we have been were awaiting them.
Have been were awaiting: lovely. I recently noted that English has no future tense, but whether the grammar of time travel would be easier if it did is a question for another day. As things stand English verb tenses, Clegg concludes, “definitely aren’t designed to cope with time travel”. This is good to already will have known.
Update:
A nice example from Futurama, season 6 episode 16, ‘Law and Oracle‘ (brief clip here):
No! No! What have I will have done?
Sentence first 
As a big fan of his work, I still think Dr Dan Streetmentioner’s tome wioll haven be the definitive work on the subject :)
Sorry for the long post, but I think it’s entirely relevant:
“The Restaurant at the End of the Universe is one of the most extraordinary ventures in the history of catering. It has been built on the fragmented remains of… it will be built on the fragmented… that is to say it will have been built by this time, and indeed has been—
One of the major problems encountered in time travel is not that of becoming your own father or mother. There is no problem in becoming your own father or mother that a broad-minded and well-adjusted family can’t cope with. There is no problem with changing the course of history—the course of history does not change because it all fits together like a jigsaw. All the important changes have happened before the things they were supposed to change and it all sorts itself out in the end.
The major problem is simply one of grammar, and the main work to consult in this matter is Dr. Dan Streetmentioner’s Time Traveler’s Handbook of 1001 Tense Formations. It will tell you, for instance, how to describe something that was about to happen to you in the past before you avoided it by time-jumping forward two days in order to avoid it. The event will be described differently according to whether you are talking about it from the standpoint of your own natural time, from a time in the further future, or a time in the further past and is further complicated by the possibility of conducting conversations while you are actually traveling from one time to another with the intention of becoming your own mother or father.
Most readers get as far as the Future Semiconditionally Modified Subinverted Plagal Past Subjunctive Intentional before giving up; and in fact in later editions of the book all pages beyond this point have been left blank to save on printing costs.
The Hitchhiker’s Guide to the Galaxy skips lightly over this tangle of academic abstraction, pausing only to note that the term “Future Perfect” has been abandoned since it was discovered not to be.” – Douglas Adams
Thanks for the backup, astraya!
I was thinking that this discussion needed a reference to Douglas Adams, but I see that it must will have been already taken care of.
Stuart, astraya: Wonderful. Thanks for this. It’s about 15 years since I read the trilogy (in five parts), and I had forgotten Adams’s great riff on the grammar of time travel.
Love the ‘Restaurant’ references. :D
In the American mid-deep south (I don’t live there; I’ve only visited), there is a phrase I’ve heard: Used-ta Could. As far as I can tell, it means, “maybe later.” As future(ish) tenses, it’s very… Past. But essentially, when someone says, “I used-ta could come over tonight” it means, roughly, “I might see you later.”
Or something.
Very. Strange.
Jonathon: Well said. I mean, well would will have said.
Mrs Fever: Used to could is dialectal, I think. It’s been mentioned once or twice on Language Log, for example in this comment on a post about multiple modals (which I’ve written about here). I like the idiom, but I’ve neither used it nor heard it in the wild.
Reblogged this on Grammaticism.
“Used to could” means “used to be able to.” It is definitely and always past tense. I’m from the deep south and have used it myself on many occasions. I’ve never heard anyone use it for future tense, and it wouldn’t make sense that way.
[…] using to go to be having depended?) I’m just glad I don’t also have to deal with the grammar of time travel […]