I think I do. — Srap Tasmaner
You are right that Jane's belief, which is true in the actual world, isn't false in the actual world, but what do you mean by saying that it can't be false in the actual world? — Michael
Option 1
It is possible that Jane's belief is actually false
Therefore, if Jane's belief is true then it is possible that Jane's belief is actually false — Michael
Option 2
It is possible that Jane's belief is actually false
Therefore, Jane's belief is actually false — Michael
Option 3
It is not possible that Jane's belief is actually false — Michael
Which option is correct? It must be one of them. — Michael
No. If Jane's belief is actually true, it can only be counterfactually false, not actually false. It's what "counterfactual" means. — Srap Tasmaner
No. If Jane's belief is actually true, it can only be counterfactually false, not actually false. It's what "counterfactual" means.
— Srap Tasmaner
You accepted here that "Jane's belief might be false" and "Jane's belief is true" can both be true, so I don't understand your objection. Do these two phrasings mean something fundamentally different to you? Obviously the second phrasing combines the premise and conclusion of the first phrasing into a material conditional, but the meaning of "Jane's belief might be false" is identical in every occurrence. — Michael
Phrasing 1:
Jane's belief might be false
Jane's belief is true
Therefore, Jane's belief might be false
Phrasing 2:
Jane's belief might be false
Therefore, if Jane's belief is true then Jane's belief might be false — Michael
Maybe I need to be even simpler. — Michael
Do you accept that both of these are possible worlds?
World 1
Jane's belief might be false
Jane's belief is true
World 2
Jane's belief might be false
Jane's belief is false — Michael
What exactly do you mean by "might be"? I cheated a little in W1, because the second premise allowed me to construe it as "not violating the law of noncontradiction." But really what is "might be" supposed to mean within a given world? — Srap Tasmaner
The skeptic claims that we might be brains in a vat. There are two different ways to interpret this claim:
1. There is a possible world where "we are brains in a vat" is true
2. It is possible that "we are brains in a vat" is true in the actual world
I think it obvious in context that they are making a claim such as 2). So with that in mind, I will rephrase the above: — Michael
3. There are possible worlds in which we are brains in vats, and we do not (or, perhaps, "cannot") know that this world is not one of those. — Srap Tasmaner
3. There are possible worlds in which we are brains in vats, and we do not (or, perhaps, "cannot") know that this world is not one of those.
— Srap Tasmaner
This is acceptable except your use of the word “know”. — Michael
I don’t understand what you’ve been arguing against. — Michael
As far as I can tell, and you'll correct me if I'm wrong, your position and your understanding of the issues involved has changed not at all since the OP, despite everything I and others have posted. You still appear to be baffled that anyone would disagree with anything you've posted and just post it again, as here. — Srap Tasmaner
It's something like ~(P & ~P). It's really that simple. — Srap Tasmaner
Maybe the problem is with the interpretation of the English sentence. These two don’t mean the same thing:
a) It is possible that I know something and am wrong about that thing
b) I know something and it is possible that I am wrong about that thing
The former is false but the latter seems possible as the arguments show. — Michael
. If Jane's belief might be wrong and if Jane's belief is true then Jane's belief is true and might be wrong. — Michael
If I know it's raining outside then I can't be wrong that it's raining outside. Knowledge entails truth. — Andrew M
You said that if we have a justified belief it might be wrong, which is true; but a justified belief is not knowledge, since knowledge is defined as a justified true belief. It is not the case that a justified true belief might be wrong. — Janus
So, either "I might be wrong" can be true even if I have a true belief or "I might be wrong" is only true if I have a false belief. — Michael
The first option is fine when understood as an expression of uncertainty as in, "I believe it is raining but I'm not certain". But not in the sense of, "My true beliefs could be false". — Andrew M
What does "could be false" mean? Either "there is a possible world where it is false" or "I am not certain that it is true". In both cases "My true belief could be false" can be true. — Michael
But there are no possible worlds where John is a bachelor and married. — Andrew M
There is a ball hidden in a box. That ball is either red or blue.
a) The ball might be red.
This proposition is true whatever the colour of the ball in the box. It is true if the ball is red and it is true if the ball is blue. — Michael
If you want to say that a) is false if the ball is blue — Michael
No, I'm saying that it is false that "the blue ball might be red", just as it is false that "The number 2 might be odd". There's a difference between conceptual and empirical claims. — Andrew M
No, I'm saying that it is false that "the blue ball might be red", just as it is false that "The number 2 might be odd". There's a difference between conceptual and empirical claims. — Andrew M
a) The ball might be red
If you accept that a) is true even if the ball is blue then you accept that there is a possible world where the ball is blue and a) is true.
And then I don't see a difference between these phrasings:
1. The ball is blue and a) is true
2. The ball is blue and the ball might be red
3. The ball is blue and might be red
4. The blue ball might be red
Do these mean different things to you, and so have different truth-conditions? — Michael
Whereas you seem to be interpreting them in a Moorean sentence sense. While such sentences can be true, no-one would ever assert them. People would either say the ball is blue (when they knew it was blue) OR say the ball might be red (when they didn't know it was blue), but not both together. — Andrew M
Yes, exactly that. Moore's paradox was the inspiration for this discussion. — Michael
No, because the number 2 is necessarily even. My examples are only ever where the truth of the claim is not necessarily true. — Michael
"I believe it is raining and it is not raining" is logically consistent and possibly true, but not something we would ever assert. — Michael
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