Thursday, October 22, 2020

A simpler formulation of the paradox of short pains

On reflection, my paradox of short pains can be simplified. Start with:

  1. Whether I have had a pain does not depend on the future.

  2. It is impossible for me to have a pain that lasts less than a picosecond.

  3. I once started to be in pain for the first time in my life.

Now imagine that the first pain in my life just started half a picosecond ago. Then anybody who has the power to annihilate me in the next quarter (say) picosecond has the power to make it be the case that I had not yet had a pain, since if they so annihilate me, then I won’t have had a pain by (2). But whether someone will annihilate me in the next quarter second is a fact about the future, so whether I have had a pain depends on the future.

To put this in Ockhamist terminology, if we accept (2), then we have to accept that facts about whether one has had a pain can be soft facts.

I like the idea of denying (1), though I think this may make presentists (and others) uncomfortable.

I also like the idea of saying that the argument equivocates between phenomenal and physical time. The duration of pain is a phenomenal duration that does not correspond in a precise way to a physical duration.


Apologetics Squared said...

For what it's worth, I'm a presentist who isn't all that uncomfortable with denying (1).

Also, I know you've pointed out elsewhere that the truth of verbal sentences depend on the future. I think that this crosses over with this post when asking whether the truth of thoughts depends on the future.
Let's say p is false and q is true. I begin thinking at some point in time that "p is true" but over the course of a small interval of time I complete my thought which ends up being "p is true or q is true." Did my thought change truth value? Or did my thought's truth depend on the future? (I could have presumably freely ended my thought differently!)

Hopefully an argument could be made forcing Open Theists to maintain that none of their thoughts are actually true. :)

Alexander R Pruss said...

That's a nice example: it makes it plausible that what thought one thinks can depend on the future. But it still seems really paradoxical that whether one is hurting---or having any other phenomenal state---depends on the future. In the case of verbally thinking "p is true" vs. "p is true or q is true", one's phenomenal state during the first part of the thinking seems to be the same regardless of how the thought ends up being completed. But how could the phenomenal state be retroactively changed? That seems very different.

I think your argument also suggests that the content (and even narrow content) of an act of thought is not an essential property of an act of thought. For in the two worlds---the one where one completes with "or q is true" and the one where one stops---the same act of thought has started, and yet it ends with different contents. It seems to me that an open futurist can live with this.

Brian Cutter said...

This is a neat puzzle. How about this solution: Statements of the form "x has a pain at t" are only ever true when "t" refers to an extended interval of time that is at least as long as the relevant minimum length (say, 50 milliseconds). We can then say that no one can have a pain lasting less than 50 milliseconds, and also, "x has a pain at t," when true, never depends for its truth on what happens after the interval t.

On this view, "I am in pain now" can be true (and doesn't depend on what happens after the referent of "now"), but only if "now" refers to a temporally extended interval of at least 50 milliseconds, but not if "now" refers to a particular instant. I think it's plausible that ordinary uses of "now" refer to extended intervals. Maybe we can stipulate that our "now"s refer to instants, but under this stipulation, maybe it's not a Moorean fact that "I am in pain now" is ever true.

I also think distinguishing phenomenal and physical time can solve the puzzle (as you suggest), but that comes with more metaphysical baggage.

Alexander R Pruss said...


I think this bites the future-dependence bullet. For suppose that I am in pain on [t0,t0+50ms]. Suppose that during [t0+5ms,t0+30ms], I (very quickly) assert "I am in pain now." On your story, what I've uttered should be true (or does it depend on what I intend by "now"? What would determine that?), and true in virtue of events taking place over [t0,t0+50ms]. But then whether what I assert was true then depends in part on events that happen after the end of my utterance (namely, events happening on (t0+30ms,t0+50ms]). And so it's still true that what I expressed was a soft fact, and that it is possible for you to make what I said to have been false.

Technical worry: Suppose that on [t0-40ms,t0+10ms] my toe hurts and on [t0-10ms,t0+40ms] my thumb hurts. On [t0,t0+5ms], I assert: "My toe and thumb now hurt." It seems that what I said was true. But the "now" can't refer to [t0-40ms,t0+10ms], as my thumb doesn't hurt then, and it can't refer to [t0-10ms,t0+40ms] as my toe doesn't hurt then. Does it refer to [t0-10ms,t0+10ms]? But neither my toe nor my thumb hurts then.

Brian Cutter said...

On the proposed story, your utterance would be true only if "now" picks out an interval that extends a bit into the future (relative to the time of utterance). I don't think that makes the asserted *fact* a soft one, since I would have thought that a fact of o's being F at t is soft only if it depends on what happens after t. (Maybe we can speak of soft now-utterances, where a statement of the form "x is F now" is soft when it depends on what happens after the time of utterance. Then we can say: your utterance is a soft utterance, but the asserted fact isn't a soft fact.)

Maybe a version of the objection is that the statement should be true even if we intend to refer to an instant, or a sub-50ms interval. I don't think it's intuitively clear one way or the other whether the statement would be true then. Given how weird the case is (involving utterances made at scales that can't be consciously registered, and where the utterance necessarily is made without any awareness of being in pain), I'm not sure we should have strong intuitions about the truth values of such utterances.

Another dualist-friendly thought: there's a fundamental property *being in pain* that we only ever have relative to extended intervals. But, ordinary usage of "pain" picks out a closely related derivative property pain*, where one has pain* at a time t iff one has (fundamental) pain at an interval that includes t.

William said...

It may be hard to understand how coming to be aware of something as a phenomenal perception may in many cases also automatically mean we come to be aware of a duration, and without an awareness that includes the duration we'd not be aware at all. Let's give two examples:

1. I hear a note sounded on the horn. I estimate the note lasted 1/10 second. A note that lasted less than "2 divided by the note's base frequency" could never be heard by me.

2. I see you turned on the hall LED light. As soon as I saw the light turn on I can estimate the switch was thrown 1/2 second ago. If the LED was only lit for 1/10000 of a second I would not have seen the light come on.

Alexander R Pruss said...


Does this require B-theory? On the A-theory, or at the very least on presentism, I would think there is a focal sense (in the Aristotelian sense of "focal sense") of "now", which refers to the really objectively present moment (the unique time that is neither past nor future). In the focal sense of "now", on this view it seems to be always false to say "I am now in pain." Only on non-focal senses of "now" could it be correct to say "I am now in pain." That seems counterintuitive.

Of course, if this requires B-theory, that's pleasing to me. :-)


I like example 1 a lot. But I want to distinguish the length of the note from the length of perception. A note that's less than one or two periods couldn't be heard as such. But it is at least conceivable that we should have a *perception* that lasts less than one period of the note. Here's a toy model of sound perception that seems conceivable to me, just very unlikely to be true: The brain gathers a short sample, maybe 50ms long, and performs a Fourier transform to determine the primary notes in the sample. It then creates qualia corresponding to these primary notes, and makes these qualia present to the mind. The *qualia* then start with a 50ms delay. And the qualia could in principle last a much shorter duration than the sample that the brain analyzed, indeed in principle they could less than a picosecond.


Here's another option that now seems to me to be pretty attractive, though perhaps only dualists can buy it: a pain quale can last an arbitrarily short length of time. But there is a minimal length of time needed for the perception to be committed to memory. So if after the first picosecond of pain one's pain were shut off, it still would have been true that we had pain--but we wouldn't remember it.

William said...

Sound shorter than one or two of its wavelengths, if strong enough, will cause the eardrum to move enough to cause a click sound in the inner ear, but there will be no pitch. Is there a way to imagine a true note in the mind for such a short time? For me, imagining a sound seems to take as long as I would hear the sound, or longer. Might even mere imagination or memory of a sound need a duration as part of its perception for the phenomenon to be conscious to us?

I can accept your last idea that such a quale could occur but would never become part of our working memory or stream of consciousness. I wonder, though, how you could ever know if the quale had been there.

Alexander R Pruss said...


The following sentence seems to make sense: "I just imagined that for the past hour I heard a humming noise -- and it took me only a second or so to imagine it." Just as an imagining of something spatial doesn't have the same spatial dimensions as the spatial thing being imagined (e.g., I can imagine a rock that's bigger than my brain), so too imagining something temporal doesn't have to have the same temporal dimensions as the temporal thing being imagined.

I agree that such a quale probably wouldn't be a part of our working memory. If we knew at all that it occurred, we'd only know this during its occurrence.

Alexander R Pruss said...

Here's another way to put it. There is a phenomenal feel to "I've been feeling pain (say) for a long time." But one could have that phenomenal feel for only a short time, without having felt any pain before.