Disagreeing that Probably p
We say things like the following quite often:
(1) Jack is probably home right now.
(2) She probably forgot her keys.
(3) I’m probably going to hell.
Now consider the following example. (More of such examples are discussed by Andy Egan in “Epistemic Modals, Relativism and Assertion”.) Suppose that on the basis of good but non-conclusive evidence that Jack is home right now, you utter (1). You seem entitled to utter (1). But I’ve seen Jack at the office just a minute ago, and know that he can’t be home right now. Overhearing what you’ve just said, I reply, “No, that’s not true”. Is my reply appropriate?
Some have quite a strong intuition that it’s appropriate. But what do I deny in replying, “No, that’s not true”? Am I denying that Jack is probably home right now, or am I denying that he is home right now? Consider the following examples:
A: It seems to me that Jack should be home by now.
B: No, you’re wrong.
C: Yes, it does seem that way to you.
A: It seems to me that philosophy is a waste of time.
B: Well, you’re wrong!
C: Yes, it does seem that way to you.
A: I think that truth is relative.
B: No, it isn’t.
C: Yes, you do think that truth is relative.
A: I believe that work is more important than exercise.
B: No, that’s not true.
C: Yes, you’re right that you have such a belief.
A: I’m quite certain that Jack is at home right now.
B: No, I’m afraid you’re wrong.
C: Yes, you’re indeed quite certain that he’s at home.
B’s replies to A seem to be very natural ones to make. But it also seems that none of them is a denial of what is said at face value. Suppose you say, “It seems to me that philosophy is a waste of time”, and I reply, “Well, you’re wrong”. Is my reply appropriate? You might think that it isn’t, if you take it to be a reply to what is said at face value; after all, it isn’t my business to set you right on how things seem to you to be. But it’s a very natural reply to make, especially in contrast with the kind of reply that C gives. In telling you that you’re wrong, I’m denying that philosophy is a waste of time, and not that it seems that way to you. (Of course, you could try to be difficult and say in response to me, “Well, I didn’t say that philosophy is a waste of time—I just said it seemed that way”.)
Question: might something similar be going on in the “probably” example? When you utter, “Jack is probably home right now”, and I say, “No, that’s not true”, am I denying that Jack is at home, rather than denying what is said at face value, namely, that Jack is probably at home?
Suppose we tweak the example slightly. Suppose I have very good but inconclusive evidence that Jack’s in his office. Now imagine that the following exchange takes place:
You say: Jack is probably at home right now.
I say: No, he’s probably still in his office. (Thanks to JC for suggesting this example.)
Since I’m not sure that Jack isn’t at home, I do not want to deny that he is. But does this show that in saying “No”, I’m denying that he is probably at home? No. For on the same grounds, we might have had the following exchanges instead:
You say: I believe that Jack is at home right now.
I say: No, I believe he’s still in his office.
You say: I’m quite certain that Jack is at home right now.
I say: No, I’m quite certain that he’s still in his office.
Both exchanges above sound rather natural. In the first exchange, it’s implausible that in saying “No”, I’m denying that you believe that Jack is at home. In the second exchange, it might not seem that I’m denying outright that Jack is at home, but it’s also implausible that in saying “No”, I’m denying that you’re quite certain that Jack is at home. Is what’s going on in the last three exchanges relevantly similar? Perhaps, saying “No” in each case is just a way of protesting that you should not believe, should not be quite certain, should not think it probable, that Jack is at home.
One more example:
You say: I have it on good evidence that Jack is at home right now.
I say: No, I have it on good evidence that he’s still in his office.
In saying “No”, am I denying that you’ve good evidence that Jack is at home? I guess the answer depends partly on my conception of evidence. If I think that my having good evidence that p is compatible with your having good evidence that not-p, then I’m not denying that you’ve good evidence that Jack is at home—perhaps, I’m just denying that Jack is at home on the basis of my evidence that he’s still in his office, or perhaps, I’m just denying that your evidence is better than mine. But if I think that my having good evidence that p is incompatible with your having good evidence that not-p, then in saying “No”, I do seem to be denying that you have good evidence that Jack is at home right now. Perhaps, what’s going on in the “probably” example is similar to what’s going here, in which case by saying, “No, that’s not true”, I’m indeed denying that Jack is probably at home.