Meeting Place

Meeting: Tuesday @ 8. Same place as last week. See you there.

--Ian

ps: here are a series of true conditionals.

1. If you go to the meeting tonight, you won't find food served. (Simple conditional?)
2. If you brought food to the meeting tonight, no one will be angry if you eat it yourself. (Compound conditional?)
3. Your host will have sodas, water, and beer if you're interested. (Biscuit conditional?)

Only slightly unrelated element

DS wrote: "here is an lsat problem. do you think it contains a fallacy?"

Sin occurs only when a person fails to follow the will of God. But since God is all-powerful, what God wills must actually be. Therefore, it is impossible to deviate from the will of God, so there can be no sin in the world.

What do you guys think? Is there a mistake in the reasoning?

We've been spammed

I've had to change our comment rules. Now, to post a comment you will have to copy a word that is generated by the site. Sorry for any inconvenience. I'm going to delete all the spam comments.

--Ian

question about NTV and deflationism...

So, I was wondering if it is necessary for a deflationist to take a NTV route with conditionals? Or would they explain its meaning in terms of a truth-predicate of some meta-language? And if that's the case, would they then use a similar type of truth predicate in the meta-language? But if they do that, it just seems like a side step to the real issue.

I'm not sure you can explain meaning in terms of use only without appealing to truth some time down the line.

Anyway, I don't know if this makes any sense or not, but if anyone can explain it to me that would be great.

-Ryan

The Second Route to NTV

Does Bennett blunder in travelling the second route to NTV? I thought he might, but there may be a way of cleaning up the argument. First, let's rehearse the second route. There are two premises that, when considered in conjunction with the notion that conditionals are propositions, leads to inconsistency. The argument denies that conditionals are propositions because the two premises are so plausible.

The Argument (Bennett, 102-3):

(1) Being certain that (A ∨ C) without being certain that A, is sufficient for being certain that ¬A → C.

(2) It is not necessarily irrational to disbelieve A yet also disbelieve that A → C.

For the first premise, although Bennett doesn't put it this way, I think it is best understood when we consider real tokens of the sentences. So, for example, (1) is very plausible when we take (A v C) to be (Either Ryan or David is guilty). We can imagine someone convinced of this claim who is not convinced that it is Ryan who is guilty. And, the combination of these two beliefs would surely lead this person to believe that If it isn't Ryan who is guilty, then it is David. If this is correct, then the first premise seems very plausible.

Understanding the second premise is not so easy. First, there is the curious construction, "It is not necessarily irrational to disbelieve ..." Using typical modal manipulation, we can push the negation through the necessity to make, "It is possibly not irrational to disbelieve ..." By double negation we get, "It is possibly rational to disbelieve ..." So, it is possibly rational to disbelieve A and to disbelieve A → C. I take it that Dave's Wayne Newton conditional is just such a case. It is possibly rational for Dave to disbelieve that he's seeing Wayne Newton live, while at the same he can disbelieve that if he is watching Wayne Newton Live, then he (i.e. Dave) is in Arizona. And, if you are convinced by Dave's claims regarding the Wayne Newton conditional, then you are poised to accept premise (2). (Bennett notes that it is irrational to disbelieve A and to disbelieve (A ⊃ C), given the truth conditions for " ⊃ ".)
The argument continues by supposing that A → C has a truth value, i.e. it is a proposition. Bennett says, "Because of premiss (2), it must be possible for A → C to be false while A is false, and thus while A ⊃ C is true. [given the truth conditions for " ⊃ "] It follows trivially that ¬ A → C could be false while ¬ A ⊃ C is true, that is, while A ∨ C is true. In that case, being perfectly certain that A ∨ C would not entitle one to be perfectly certain that ¬ A → C, and so premiss (1) would fail." (Bennett, 102)

Since (1) is so plausible, it must be the supposition that A → C is a proposition that is at fault. So, we jettison that supposition to arrive at NTV (conditionals are not propositions, they don't have truth values).

I see two possible problems for the argument as stated. First, and though almost nobody else thinks this, it is possible that "∨" does not capture English "or". If this is true, then the claims about what someone believes when they believe "A ∨ C" etc., would need revision.

Second, and perhaps more devestating, the premises are couched in terms of epistemology: certainty, rationality, and belief. Yet, we are supposed to draw a metaphysical conclusion from them: conditionals aren't propositions. Unless we can recast the premises wholly in terms of truth values, the argument makes an intro to philosophy blunder.

Revised premises:

(1') If (A v C), then (¬ A → C)

(2') Possible that ¬A and ¬ (A → C)

From (2'), and substituting ¬ A for A, it's possible that both A and ¬ (¬ A → C). Suppose we are in such a situation. From A we get (¬ A ⊃ C).

But, If (¬ A ⊃ C), then (A ∨ C).

And, by (1'), if (A ∨ C), then (¬ A → C).

So, by hypothetical syllogisim, if (¬ A ⊃ C), then (¬ A → C).

But we know it is possible that ¬(¬ A → C).

Remember our supposition. Both A is true and (¬A → C) is true. But the argument leads to its negation ¬ (¬ A → C) (i.e., its falsity).

We get a contradiction, but it doesn't seem as obvious that it is the proposition interpretation of conditionals that is to blame. Maybe it is the paradox of material implication that is to blame. Or, as I stated earlier, the "∨" to "or" move.

You can see Bennett's claims regarding how Adams avoids the problems of the second route on p. 102-103.

Post your comments, suggestions, etc. in the comments section please.

--Ian

Reading for July 18 (with questions)

Read Bennett up to p. 69 + his two pages on "Even If".

Questions for next meeting:

1. Glen gave the following pair of "even" sentences:

(a) Even Hamas admits that Isreal exists.
(b) Even Hamas admits that Isreal has the right to exist.

He claimed that (a) is true and (b) is false. How do we determine the truth-value of an "even" sentence?

2. Suppose that Jesse says:

(c) UNLV will cancel philosophy of science if only three people register.

Suppose Mark thinks that Jesse's claim is false. Which of the following two sentences correctly captures Mark's denial, and why?

(d) UNLV won't cancel philosophy of science if only three people register.
(e) UNLV won't cancel philosophy of science EVEN if only three people register.

3. Do EVEN IF statements entail their consequents? (Reread Jackson on "even if" if you are having difficulty with this question).

Remember we are going to meet on Tuesday @ 8pm AND Wednesday @ 8pm!

--Ian

Where are the posts?

Howdy Folks,

I was expecting to see some interaction on the blog while I'm away.

Submit something - questions, comments, what-have-you.

--IJD