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On Regret and Slingshots

Tuesday, May 2, 2006 at 10:18PM

Here’s a silly puzzle for you.

Regret seems like a factive emotion. You can’t truly regret that you forgot to feed the cat today if, indeed, you did feed the cat. If you did feed the cat and you forgot that you did, then it seems to you like you’re regretting not feeding the cat, but you’re as mistaken about your regret as you are about feeding the cat. You think you didn’t feed the cat and you’re sorry that you didn’t, but that’s not regret. Or so some people think, anyway.

Now, suppose that regret is factive like that. Then it’s plausible to think that the circumstance you’re regretting is in some way a ‘component’ of that regretting. (On this view, that’s why it’s factive: if the circumstance of my not-feeding-the-cat isn’t there, then I can’t be related to that circumstance in “regretful” manner.)

If this is the case, then it’s plausible to think that disjunctive regrets are a strange sort of thing. Regretting that p or q might be a relationship to a situation in which p is true (when it’s the truth of p that makes the disjunction true) or one in which q is true (the other case). A regret that p or q might be the same kind of thing as a regret that p (if p is the case) or a regret that q.

So, let’s suppose that in general, a disjunctive regret that p or q – since it is a regretting relationship to a circumstance in which p or q is true – brings with it a regret that p or a regret that q, since either the p-or-q circumstance is one in which p is true, or it’s one in which q is true. Call this the disjunction principle.

Now, it seems that regretting that (p and q) and regretting that (q and p) are no different to one another. Similarly, regretting that (it’s not the case that (p and q)) is no different to regretting that (either it’s not the case that p or it’s not the case that q) and so on. It seems a little bit plausible that if A and B are two statements that are logically equivalent then regret that A and regret that B don’t differ. Call this the equivalence prinicple.

Oh, suppose that the classical story of logical equivalence, that you were taught when you were taught truth tables, is correct. This is enough to get the puzzle going.

These things can’t all be right. Unless you have a lot on your mind. Here’s why.

Suppose you regret that p. Then, p is logically equivalent to (either (p and q) or (p and not q)). So, your regret that p means that you also regret that (either (p and q) or (p and not q)), by the equivalence prinicple. By the disjunction principle, you either regret (p and q) or you regret (p and not q). Suppose, without loss of generality, that it’s (p and q). Now (p and q) is equivalent to ((p and q and r) or (p and q and not r). So by the eqiuvalence principle … You see how it goes.

This is a version of the slingshot argument for regrets. Clearly, you shouldn’t believe the equivalence thesis (in its classical guise, at least) and the disjunction thesis for regrets. I’ve argued before in favour of the disjunction thesis and against classical equivalence for truthmakers.

What should we think in this case? Are either of the equivalence or the disjunction theses plausible? I’ve got my own ideas but I’ve written enough for one night.

(Thanks to Robert Anderson for getting me thinking about regrets and disjunctions and proposing something like the disjunction thesis. He thought of it when worrying about bets and regrets and Lloyd Humberstone’s puzzle mentioned in the previous post.)

News Archive

2002 | 2003 | 2004 | 2005 | 2006 | Happy 2006Teaching in Semester 1, 2006Assorted crosscultural observations, upon visiting the supermarketPhase ChangeFun with Playlists: Squeezing your music library onto a 2GB iPodDegrees of Truth, Degrees of FalsityMasses of Formal PhilosophyGreg Hjorth coming back to MelbourneMarathon EffortLast Night at the MCGDame Edna at the Commonwealth Games Closing CeremonyBeing a logician means sometimes having to say that you're sorry. Or at least, that you're wrong.Oh, and there's another paper, tooSpooky coincidence? I think notAJL Papers2006 redesign in progressEnclosuresThe Shifty SalesmanWell, that was easy...Happy 5 day!Masses of Formal Philosophy: Question 1On the Cable Guy ParadoxOn Regret and SlingshotsEnd of SemesterInterviewedThis football game is pretty tense...Key Ideas in the theory of proofs #1: The Duality of Proofs and CounterexamplesTeaching in Semester 2, 2006Off to FranceHere in Nancy, Day 1Here in Nancy, Day 2Back homeAssorted ObservationsInterviewed againOn PoliticsOn the InterviewTen Questions about BooksVisitsAn idea...Masses of Formal Philosophy: Question 2Party on TuesdayA Philosophical Poll: on a priori knowledge of possibilitiesHorn tootingScenes from an afternoonOff to India...2007 | 2008 | 2009 |

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About

I’m Greg Restall, and this is my website. I work in Philosophy at the University of Melbourne. Email: greg at consequently.org; Post: School of of Philosophy, Anthropology and Social Inquiry, University of Melbourne, Parkville 3010, Australia.

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Thought

When I started writing this book, I intended to explain in the preface that this was the history of epistemology since Kant, the way Carnap would have written it had he been Hegel.
— Alberto Coffa’s preface to The Semantic Tradition from Kant to Carnap.