Doesn't anyone understand the concept of time?
My response to the title question1 was essentially 'Somewhat, yes', at which point I felt the need to define it as best I could.
Time is a full-sized dimension for which causality, for the most part (as we typically perceive it, and as it causes our perception)2 is uni-directional.
Traditionally I thought of space-time as four dimensions through which we were travelling at a constant speed, and where we would by default be travelling that speed one direction through time. But recognising the causality of perceptions made me realise that's really stupid. (My excuse is that it's from my high school days or earlier. No excuse for not moving well past it years ago. I did kind of move past it, but didn't completely abandon it.) Obviously we're not 'moving through time' (or maybe we are because, well, that's how we define movement), but because my current state is caused by my past state, the past appears to me as, well, the time.
In metaphysics, we discussed timeslices and how this stuff doesn't degrade into nominalism. (My position was that it does and that it's good that it does because nominalism is the view that actually makes sense.)
This newish line of thought lead me to determinism. It always seemed baseless and strange to me what people say that if determinism is true, that Laplace's demon can calculate not only the future, but also the past. Clearly, were determinism true then a given timeslice of the universe could lead only to one outcome, but why could there not be multiple timeslices that can cause a given timeslice? Consider Conway's Game of Life. The blank board, for example, can be caused by:
* The blank board
* The blank board with exactly one cell, located at at 0,0
* The blank board with exactly one cell, located at at 0,1
* The blank board with exactly two cells, located at at 0,0 and 47,42
* And so on.
This doesn't only apply to the blank board, of course. Any board causes by board X can also be caused by board X with one lone cell added apart from all the others.
Clearly, the universe is not governed by the rules of Conway's Game of Life, but it seems as if the principle should be similar. (I suppose my examples should have been selected to agree with the conservation of matter and energy, but that's more complicated. Still entirely doable, though.)
As I wrote this, though, something I missed earlier struck me: the verificationist would claim that 1. the claim that those vanishing cells exist/existed is meaningless and more importantly (because 1. is addressed by my comment in my previous parenthetical) 2. the claim that a given timeslice that could cause our current one existed and that another potential causing timeslice didn't is meaningless.
I have a lot of sympathy for verificationist. But they're so very annoying, don't you agree?
1 Not that anyone asked it. It just popped into my mind.
2 Initially I went with 'for normal matter', but I didn't like that at all.