Mathematical truths do behave like causes. Remember, Bayesian probabilities represent subjective uncertainty. Yes, my uncertainty about the Riemann hypothesis is correlated with my uncertainty about other mathematical facts is the same way that my uncertainty about some physical facts is correlated with my uncertainty about others, so I can represent them both as Bayesian networks (really, one big Bayesian network, as my uncertainty about math is also correlated with my uncertainty about the world).
Mathematical truths do behave like causes. Remember, Bayesian probabilities represent subjective uncertainty. Yes, my uncertainty about the Riemann hypothesis is correlated with my uncertainty about other mathematical facts is the same way that my uncertainty about some physical facts is correlated with my uncertainty about others, so I can represent them both as Bayesian networks (really, one big Bayesian network, as my uncertainty about math is also correlated with my uncertainty about the world).