If there is a 70% chance a certain occurrence might happen, does it have any chance of happening?

There must be a 100% chance that something might occur for it to have any chance of occurring.

If there's less than a 100% chance, then might is no longer might, but only a chance of might, which is itself only a possibility. If it's not 100% possible, then the occurrence is not possible, because possibility has to be for sure for something to be possible

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    Oh sorry I misread "if there iess than". Any event with a chance greater than 0% can happen, but only 100% means it will happen. TBH I'm baffled by this question. Sep 22 at 19:29
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    Please clarify your specific problem or provide additional details to highlight exactly what you need. As it's currently written, it's hard to tell exactly what you're asking.
    – Community Bot
    Sep 22 at 19:36
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    Yes, it has a 7 out of 10 chance of happening. It can happen, but it might never happen. No one will ever find truth by excluding common sense and self-evident truth from their resources! Sep 22 at 19:54
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    There's no chance that this question will not be closed.
    – Scott Rowe
    Sep 23 at 0:08
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    It’s difficult to see how this question is useful to users at Philosophy.SE - if there’s a 70% chance it will rain tonight, then logically, it is then possible it will rain tonight. We need a context to understand why this is being asked (that is, why the intuitive answer might be faulty).
    – Hokon
    Sep 23 at 0:12

1 Answer 1


The probability of something happening when added to the probability of it not happening always comes out to be one.

Probabilities tell you what the odds are for a certain outcome in a trial which means they only make sense in the context of many, many trials. Probabilities cannot be used to predict the exact outcome of any trial; a 40% probability of a specific outcome only means that out of ten trials, 4 of them will come out that way- on average.

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