There may be a certain probability that a particle will have decayed after a certain period of time. There is nothing compelling it to have decayed by that time, and indeed it may not do so. But perhaps it is more likely to decay by that time than not. It has a propensity to do so. And when it does so, there seems no contradiction in the idea that the propensity caused the decay, even if it didn’t guarantee it.
Probablistic. Main. Anscombe
