To celebrate the 101th post on Arete, it seems appropriate to discuss time travel. After all, if we could travel back in time to view the first post being written, would that not be an exciting event?
This post will largely be responding to a paper by Rupert Read found here. I would highly suggest reading it, although you should be able to get the gist without doing so.
I have several concerns about Read's arguments, and will address them here.
1. He asserts that "there seems no good reason to withhold the term
“time-travel” from healthy, body-renewing sleep, especially perhaps
if it is relatively dreamless. You really can travel to the future. You
can see the future.You can be there. Just by going to bed; just by
living long enough" (Part I, Section 8). I agree with this proposition-- we are, in fact, traveling through time. However, as you'll see, I believe his argument about the "why" is wrong.
2. Read asserts that what "in sleep is missing from time-travel is the essential element of any travel worthy of the name, of tourism and holidaying for instance: the ability, at least, to go there and back again" (Part I, Section 10). This is absolutely incorrect. It would be a radical sort of time travel to go far into the past without a method of return. This may be correct for future-oriented time travel (as the act of sleep would seem to imply), but this fails to account for the novelty of past-oriented time travel.
3. Read establishes a straw man in order to attack past-oriented time travel: he asserts as an axiomatic premise that "you already know that there is no record in the past of you having been there, nor of anyone else from the future, no matter how distant or technologically-sophisticated that future becomes" (Part II, Section 4). There is no need to assume this. Suppose that, in the present, you find clear signs that the time traveler changed nothing; they had already (and always) traveled back in time. Many fictional works, such as 12 Monkeys and Doctor Who, take this as essential.
4. Read asserts that, "in order not to have changed the past, and made it something other than the very thing that you wanted to voyage into, you cannot have had any impact at all, not even one so slight that it evaded all records and notice" (Part II, Section 6). This is a false dichotomy, as explored in my third argument. It's possible to have changed nothing in the past, and yet not evaded notice.
5. Read asserts that "travel back into the past is only possible if the “you” that does the travelling is entirely ethereal. Nonphysical. For the slightest impact upon the past will generate a 'causal loop,' and thus a familiar paradox of time-travel" (Part II, Section 7). The real substance of this paper should have consisted in explaining the "causal loop" and how it results in an absurdity. To hinge arguments upon this assumption is to assume something essential to the outcome.
6. Read's criterion of falsifiability seems to be as follows: "For what was necessary in order for us to be willing to call something “time-travel” (namely, its being meaningful to speak of travel “back into the past”) is just not available. Our relation to the past is necessarily spectatorial, in a doubled sense: We cannot interfere with it, and we cannot even observe it except from a temporal distance" (Part II, Section 15). This unintentionally raises a huge problem for Read. He states that we cannot call travel "time travel" that which we cannot interfere with, unless we can interfere with it directly. However, we cannot directly interfere with the future; we must wait for it to become the present. Thus, we do not travel through time into the future. This directly contradicts Part I, Sections 5-10, and limits the significance of his arguments against future-oriented time travel.
7. Read oversimplifies the complex issue of the indeterminacy of the future: "The past is very largely determinate, fixed, just by virtue of its being past: and “travelling back into it” requires that it not be fixed. The future is to a considerable extent open just by virtue of its being future" (Part III, Section d). This raises a host of issues, problems, and questions; if this is to be treated as an axiomatic assumption, it should be addressed at the outset, and the validity of his findings should noted to be contingent upon it.
So, what do you think? Am I being too hard on Professor Read, or are my critiques legitimate? Thanks for your comments!
This post has been edited to resolve potential formatting issues.
Friday, September 30, 2011