[HelloNurse]

That highly probable events actually happen can be a reasonable practical assumption, but definitely not a logical certainty. It is the hard, probabilistic version of the sorites paradox: with few atoms and little time, any chemical process is unlikely; with a whole planet and a few billion years, chemical processes are very likely; at some intermediate sample size you can feel justified to assume that what you are interested in happens, but it is only a feeling, not a real qualitative threshold.