Monday, August 23, 2010

Assertion and belief: Another example

Either if N is a supermanifold, then there is a space ΠT*N of the cotangent bundle with reversed parity and it has a natural structure of a P-manifold, or it is not the case that if N is a supermanifold, then there is a space ΠT*N of the cotangent bundle with reversed polarity and it has a natural structure of a P-manifold.[note 1] I just asserted a proposition which I don't believe. Indeed, I don't even grasp this proposition. But, nonetheless, the proposition is surely true, because it is a tautology. (I suppose there is the possibility that the sentence doesn't make sense. There, I take it on Alexandrov's authority[note 2] that it makes sense.) I did not violate any duties of sincerity in asserting the sense.

Hence, sincerity in assertion does not require belief.

If s is the first sentence of this post, I can correctly say: "s but I do not believe that s." And so some Moorean sentences are unproblematic.


enigMan said...

Suppoe I believe that either p or not-p, for all p.
Then in particular I believe it in the particular case of p = P.
So I might sincerely assert S = either P or not-P.
But I would be doing that because I believe that S, because P is such a p.
It might be that I don't grasp P, just having it on good authority that P is such a p.
Basically, I don't see why you think that you don't believe the s of your example.
I think that we might grasp a proposition well enough to believe it without fully grasping all of its parts.

James Bejon said...

I'm not sure I see why you can say:

s but I do not believe that s,

since it seems you can believe a proposition without knowing much about its content. Take, for instance, the following

Either sum(a(1),..,a(n)) = k or sum(a(1),..,a(n)) =/= k

It seems I can believe this proposition without knowing anything about any of its variables.

James Bejon said...

...or of course you could just read enigMan's post which says pretty much the same thing...

Alexander R Pruss said...

Well, in this case, I didn't even have the whole sentence in my mind at once. I just copied and pasted. And one can do the same sort of thing in speech--just parroting bits of text. I don't know that I count as believing something just because I've pasted it in and think it's true.
Consider that there are, plausibly, rational connections between beliefs and beliefs/actions. But if we allow belief with such fragmentary grasp as you're allowing in these cases, then these connections seem to disappear. For instance, let's say I take some complicated scientific sentence to be true on authority, but I have basically no grasp of it. I can't even parse it and figure out what is a noun and what is a verb. But I say the sentence, since I believe it's true. If I count as believing the proposition expressed by the sentence, shouldn't I then be held to the rational consequences of believing it, such as guiding my action by it, taking it into account in my reasoning, etc.? But I can't really do that.

Maybe this is just London/Londres all over again, though.

Heath White said...

Here is another possible interpretation: you asserted it, and you believe it, but you don't understand it. It seems like there is a kind of chain here

understanding -> belief -> sincere assertion

where it might seem that each thing on the left is a necessary condition for what's on the right. You wish to break the chain at the second link; I think it can be broken at the first. Maybe it can be broken in both places.

Alexander R Pruss said...

I think that's helpful, but I am not sure it works in all cases.

For instance, suppose I highlight what I believe to be a grammatical sentence in someone else's text, and copy it into a clipboard without reading it. I then paste the sentence, delete the period, type " or it is not the case that ", paste the sentence again, decapitalize the second instance, and then post. And I do this without ever reading the sentence I pasted in. In doing this, I followed a procedure that I knew would result in a truth. But it is truth I have never read--I've simply used a quasi-automated method (it could have been completely automated with a keyboard macro--highlight, press ctrl-alt-T, and the tautology is inserted into a post). It seems odd to attribute belief of it to me.

Let B be a book of the Bible such that I have good reason to think each sentence of it is an assertion, but where I haven't actually read anything from the second chapter of B, nor even heard it quoted. Suppose also, correctly, that I believe in inerrance. Then I believe that the fourth sentence of the second chapter of B is true. But it would be mistaken, I think, to attribute to me belief in the proposition expressed by the fourth sentence of the second chapter of B. Suppose now that I open the second chapter of B on my screen, and squint my eyes so I can't read the words, but I can see where sentences begin and end. I highlight the sentence, and paste into my post, still without reading it. In terms of normative consequences, I've asserted it. But it seems implausible to suppose that just by copying and pasting the sentence, I came to believe the proposition. So, either I don't believe it after the copy and paste, or I believed it before even opening B.

I am inclined to think that these sorts of cases show that we should replace the concept of assertion with the concept of (assertoric) endorsement. (I have a paper I'll be presenting at the ACPA on this.) Sincere endorsement of a sentence does not require that I believe the proposition expressed by the sentence, but only that I believe it to be true. One way to endorse a proposition is to assert it in the normal way. But one can also endorse in other ways. For instance, if I sign an assertoric letter you've written, I endorse its contents. And I can sincerely endorse its contents whether or not I believe them (e.g., I don't need to read the letter if I trust you enough on this subject and you've told me the general outlines), if I believe the contents to be all true (the exact details have to be more complicated; because of the preface paradox, it's not necessary that I believe the contents to be all true).

James Bejon said...

Perhaps in such cases (where s is the cut-and-pasted assertion in question) one should say:

'I believe that either p or not p' and 'I believe s to be an assertion'

So perhaps I agree that one can say

X but I do not believe that X

(Or perhaps I don't agree at all. Perhaps I just cut and pasted this entire post from online somewhere)

Heath White said...


I agree that your cases show that one can (sincerely) assert that p without believing that p. Also, if you don't pay attention in the relevant ways, there may be no 'p' such that you believe that 'p' is true, even though you are sincerely asserting that p. (Presumably there does have to be some definite description D such that you believe that the proposition or sentence described by D is true. It would be interesting to push on this assumption.) So I'm on board so far. My earlier comment was just pointing out an additional possibility.

I'm a little puzzled, though, why you think this requires you to abandon the concept of assertion. Why isn't assertion = assertoric endorsement? Or in other words, you seem to think that (sincere) assertion requires belief, but assertoric endorsement does not. It seems to me, rather, that you've shown that assertion does not require belief.

Alexander R Pruss said...

I meant: abandon as a sui generis category.

I like your variant where there is no proposition p. Here's another variant: Surely I can sincerely assert nonsense. Philosophers sometimes do.

Alexander R Pruss said...

Actually, on reflection, I don't know that it is possible to assert nonsense.

James Bejon said...

But if cutting and pasting s from a paper counts as asserting a meaningful claim, then why can't cutting and pasting a sentence from the Jabberwocky count as asserting nonsense?

Alexander R Pruss said...

One doesn't assert sentences. One asserts propositions. Nonsense isn't a proposition. So one can't assert nonsense. One CAN quasi-assert nonsense. :-)