What prevented the attempts from succeeding was not the idea itself but the way it was articulated formally. Almost without exception, philosophers expressed the sentence “X raises the probability of Y” using conditional probabilities and wrote P(Y | X) > P(Y). This interpretation is wrong, as you surely noticed, because “raises” is a causal concept, connoting a causal influence of X over Y. The expression P(Y | X) > P(Y), on the other hand, speaks only about observations and means: “If we see X, then the probability of Y increases.” But this increase may come about for other reasons,
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