To me, the fundamental point isn’t probabilities, it’s that you need to make a choice about what you do. If I have the option to give a $1mn grant to preventing nuclear war or give the grant to something else, then no matter what I do, I have made a choice. And so, I need to have a decision theory for making a choice here.
And to me, subjective probabilities and Bayesian epistemology more generally, are by far the best decision theory I’ve come across for making choices under uncertainty. If there’s a 1% chance of nuclear war, the grant is worth making, if there’s a 10^-15 chance of nuclear war, the grant is not worth making. I need to make a decision, and so probabilities are fundamental, because they are my tool for making a decision.
And there are a bunch of important question where we don’t have data, and there’s no reasonable way to get data (eg, nuclear war!). And any approach which rejects the ability to reason under uncertainty in situations like this, is essentially the decision theory of “never make speculative grants like this”. And I think this is a clearly terrible decision theory (though I don’t think you’re actually arguing for this policy?)
To me, the fundamental point isn’t probabilities, it’s that you need to make a choice about what you do. If I have the option to give a $1mn grant to preventing nuclear war or give the grant to something else, then no matter what I do, I have made a choice. And so, I need to have a decision theory for making a choice here.
And to me, subjective probabilities and Bayesian epistemology more generally, are by far the best decision theory I’ve come across for making choices under uncertainty. If there’s a 1% chance of nuclear war, the grant is worth making, if there’s a 10^-15 chance of nuclear war, the grant is not worth making. I need to make a decision, and so probabilities are fundamental, because they are my tool for making a decision.
And there are a bunch of important question where we don’t have data, and there’s no reasonable way to get data (eg, nuclear war!). And any approach which rejects the ability to reason under uncertainty in situations like this, is essentially the decision theory of “never make speculative grants like this”. And I think this is a clearly terrible decision theory (though I don’t think you’re actually arguing for this policy?)