I'm not sure if this is related, but I believe there are very deep open questions in probability (eg.: the interpretation of probabilities based on counter-fact

I'm not sure if this is related, but I believe there are very deep open questions in probability (eg.: the interpretation of probabilities based on counter-factuals) and it's what came to mind: https://en.wikipedia.org/wiki/Probability_interpretations https://en.wikipedia.org/wiki/Probability_interpretations