Who shot JFK?

[ciphergoth]

For the purposes of this post, I don't really care who shot JFK; it's just a convenient mystery with which I can ask a question about truth.

Alice believes that Lee Harvey Oswald shot JFK. She believes that Lee Harvey Oswald was in the Texas Book Depository, aimed a loaded rifle and shot JFK, at which point his head visibly exploded as seen in the Zapruder video.

Bert disagrees; he doesn't know for sure who shot JFK, but the one thing he's sure of is that Lee Harvey Oswald was not pointing a loaded rifle out of the window of the Texas Book Depository at the President at the fateful moment.

What do I believe? As I say, I neither know nor care, but there's one thing I know for sure: one of Alice or Bert is wrong. In sufficiently weird conditions both of them might be wrong, but one of them is wrong for sure. We may never know which of them is wrong, but at least one of them is definitely wrong.

Does anyone disagree with this?

Comments

[drdoug.livejournal.com]

The question all this discussion has missed is: Where is Bob, and what has Bert done to him?

[djm4]

That would certainly be my position, for what it's worth.

Re: In which case...

[drdoug.livejournal.com]

True indeed - but I think that means that ciphergoth's position that "at least one of them is definitely wrong" might well be perceived by the participants as the least accurate of the three starting positions.

[valkyriekaren.livejournal.com]

He's shacked up with Ernie.

Obviously.

[drdoug.livejournal.com]

It would explain the communication issues Alice was always having with Bob - all that secrecy.

Re: In which case...

[djm4]

I agree, and I do think that's an important point, but that wasn't what I thought was being asked by ciphergoth.

[valkyriekaren.livejournal.com]

No, it's fine, Bob and Bert are both bisexual.

[bathtubgin.livejournal.com]

My tenpenneth, for what it's worth. From reading the comments above, I get the feeling that most people are coming at this from a different angle to me, but you've taken me right back to the epistemology questions that I studied in A103.


In brief: Yes. At least one of them is wrong, but that does not necessarily mean that at least one of them is right.

[bathtubgin.livejournal.com]

I now have the phrase 'justified true belief' wiggling round in my brain and thoroughly wearing me out.

[thekumquat.livejournal.com]

It depends on whether each of those clauses in their belief is independent of the others. If Alice states (LHO_location + rifle_aimed_by_him + JFK_went_bang), and the three points are deemed by her to be parts of one whole position, as soon as Bert (Bob's day off?) states (LHO_location_elsewhere) *or* states (rifle_aimed_elsewhere), one of their positions doesn't stack up.

How this translates from formal logic into the muzzy-headed ways people deal with the real world and the vague English language is a whole nother question - is the angle of the rifle sticking point, or the motive, or the exact position of LHO?

So I agree that one of them is definitely wrong in some respect, but how far that gets us with (for example) solving the murder, is a different question.

[adjectivemarcus.livejournal.com]

I had perceived it to be in the past too, but...

[djm4]

Then, of course, you need to consider Gordon and Harriet's little disagreement over whether or not the square root of minus one exists. Which is further confused by the fact that Ichabod doesn't even accept that minus one itself exists. ;-)

[cairmen.livejournal.com]

Having a pomo moment, Paul?

[naath.livejournal.com]

I think in the limited case of a fact that could in principle be externally verified (the location of LHO at the crucial moment, what make/model of gun(s) was/were fired from where, at what time, by who - are all things not generally given to quantum fluctuations or existential confusion) had we carefully recorded the scene (we do not actually have these facts of course, and besides it was JFK who shot JFK as any Red Dwarf fan should know) - in this limited case I think we can say that one, or both, of Bert and Alice are incorrect in at least one point. Of course it may turn out that they are both correct on what they each consider to be the important point (it was LHO, but from someplace else - as others have said).

[ciphergoth.livejournal.com]

Quite the reverse :-)

[werenerd.livejournal.com]

most certainly

[jhg.livejournal.com]

No, you are quite correct.

However, for absolute clarity and precision, I would reword the paragraphs so the mutually exclusive and exhaustive premises do the work for which they are intended.

[ciphergoth.livejournal.com]

I wish this wasn't necessary; I wish people would address the core of a philosophical example rather than tugging at the edges. Of course as you say one can strengthen the edges but it's dull and wordy work and it's hard to feel it really serves people.

[adjectivegail]

Geunine question: in our normal routine and usually mundane daily lives, here and now, does it matter?

[henry_the_cow]

To be a smart alec: it depends on whether you are using classical logic or constructivist logic, i.e. on whether you believe the law of the excluded middle. This is the axiom that says "P or Not(P)" is true. It really is an axiom; it can't be deduced from the other axioms of first-order predicate logic.

But for practical purposes, yes, I believe one of them must be mistaken about the facts (although not necessarily their conclusions, nor about their reasons for believing as they do given the evidence available to them).

[drdoug.livejournal.com]

Isn't that precisely the work that a philosophical example can helpfully do, though? By doing the edge-fiddling and word-sharpening, you get a better understanding of what the issues are and how they might be resolved, and the distance from the real-world example helps you do that without getting tangled up in every single last detail. (Of course, there's then the very hard work of translating the implications of your deliberations back to the real world ... but who said philosophy had to be easy?)

[ciphergoth.livejournal.com]

Sometimes it's that way, sometimes it's nitpicking. For example, if I'm setting up a moral dilemma asking whether you pull the lever to divert the train, I don't really want to have to set out in detail why you can't rush to where the people on the tracks are and rescue them, etc; I'd like all that to be taken as read and skip straight to the meat of the dilemma.

[djm4]

It's not at all obvious to me what the meat of the dilemma is here; I have a sneaking suspicion that it's only obvious to you because you're trying to prove a particular point, but even knowing which point you're trying to prove (as I now do), I still can't be sure which replies here (if any) you think are addressing the core and which are tugging at the edges. I do think most people - probably everyone - have been trying to discuss this in good faith.

[ciphergoth.livejournal.com]

All both true and fair - thanks David.

[http://users.livejournal.com/_lj_sucks_/]

It's also possible to have an example where everybody agrees on the definitions, but they all disagree on what the facts are. For example, Fred thinks licorice is delicious, Jim thinks licorice is disgusting.