It might be that he can’t be wrong about that, even though he doesn’t know for sure that he can’t be wrong about it. Infallibility and certainty are distinct concepts.
Certainty (confidence, etc.) is in the mind. Fallibility isn’t; you can be prone (or immune) to error even if no one thinks you are.
The point is that ‘What if I couldn’t be wrong about it?’ does not express ‘What if I could be certain that I couldn’t be wrong about it?’; the latter requires that 1 be a probability, but the former does not, since I might be unable to be wrong about X and yet only assign, say, a .8 probability to X’s being true (because I don’t assign probability 1 to my own infallibility).
Certainty (confidence, etc.) is in the mind. Fallibility isn’t; you can be prone (or immune) to error even if no one thinks you are.
Though no one could ever possibly know. Seriously: fallibility is in the mind. It’s a measure of how likely something is to fail; likelihoods are probabilities—and probabilities are (best thought of as being) in the mind.
You could be wrong about that.
What if I couldn’t be wrong about that?
Then you would clearly be immune to hemlock, and therefore weigh the same as a duck.
Then you would be 100% certain—and 0 and 1 are not probabilities.
It might be that he can’t be wrong about that, even though he doesn’t know for sure that he can’t be wrong about it. Infallibility and certainty are distinct concepts.
Fallibility is in the mind.
Certainty (confidence, etc.) is in the mind. Fallibility isn’t; you can be prone (or immune) to error even if no one thinks you are.
The point is that ‘What if I couldn’t be wrong about it?’ does not express ‘What if I could be certain that I couldn’t be wrong about it?’; the latter requires that 1 be a probability, but the former does not, since I might be unable to be wrong about X and yet only assign, say, a .8 probability to X’s being true (because I don’t assign probability 1 to my own infallibility).
Though no one could ever possibly know. Seriously: fallibility is in the mind. It’s a measure of how likely something is to fail; likelihoods are probabilities—and probabilities are (best thought of as being) in the mind.