There’s nothing in being a rationalist that prevents you from considering multiple hypotheses. One thing I’ve not seen elaborated on a lot on this site (but maybe I’ve just missed it) is that you don’t need to commit to one theory or the other, the only time you’re forced to commit yourself is if you need to make a choice in your actions. And then you only need to commit for that choice, not for the rest of your life. So a bunch of perfect rationalists who have observed exactly the same events/facts (which of course doesn’t happen in real life) would ascribe exactly the same probabilities to a bunch of theories. If new evidence came in they would all switch to the new hypothesis because they were all already contemplating it but considering it less likely than the old hypothesis.
The only thing preventing you from considering all possible hypotheses is lack of brain power. This limited resource should probably be divided among the possible theories in the same ratio that you’re certain about them, so if you think theory A has a probability of 50% of being right, theory B a probability of 49% and theory C a probability of 1%, you should spend 99% of your efforts on theory A and B. But if the probabilities are 35%, 33% and 32% you should spend almost a third of your resources on theory C. (Assuming the goal is just to find truth, if the theories have other utilities that should be weighted in as well.)
The only thing preventing you from considering all possible hypotheses is lack of brain power. This limited resource should probably be divided among the possible theories in the same ratio that you’re certain about them
Likelyhood is one consideration when determining how much to investigate a possible hypotheses but it isn’t the only consideration. Quite often the ratio of attention should be different to the ratio of credibility.
There’s nothing in being a rationalist that prevents you from considering multiple hypotheses. One thing I’ve not seen elaborated on a lot on this site (but maybe I’ve just missed it) is that you don’t need to commit to one theory or the other, the only time you’re forced to commit yourself is if you need to make a choice in your actions. And then you only need to commit for that choice, not for the rest of your life. So a bunch of perfect rationalists who have observed exactly the same events/facts (which of course doesn’t happen in real life) would ascribe exactly the same probabilities to a bunch of theories. If new evidence came in they would all switch to the new hypothesis because they were all already contemplating it but considering it less likely than the old hypothesis.
The only thing preventing you from considering all possible hypotheses is lack of brain power. This limited resource should probably be divided among the possible theories in the same ratio that you’re certain about them, so if you think theory A has a probability of 50% of being right, theory B a probability of 49% and theory C a probability of 1%, you should spend 99% of your efforts on theory A and B. But if the probabilities are 35%, 33% and 32% you should spend almost a third of your resources on theory C. (Assuming the goal is just to find truth, if the theories have other utilities that should be weighted in as well.)
Likelyhood is one consideration when determining how much to investigate a possible hypotheses but it isn’t the only consideration. Quite often the ratio of attention should be different to the ratio of credibility.