But not the other way around. And it is semantics and proper word usage. Semantics is a real thing, and is useful in presenting ideas properly. "Probably" is not necessarily a synonym for "Possibly" unless you know the odds, and if they are greater than 50%. You used "probably" when you should have used "Possibly", and by doing so you actually changed the logic of your idea from one that may have some (maybe real low, even say, 1 in a trillion?) chance of occurring to one that more than likely (at least 51% chance) did happen. You should have used "possibly" to be accurate because you didn't not know that it was "probable", only that it was "Possible".
It is appropriate to check the definitions of each:
Probable:
http://www.dictionary.com/browse/probable?s=t
Possible:
http://www.dictionary.com/browse/possible?s=t
Thanks for the French lesson. It is possiblement that this will be helpful this summer when I visit France. Not probablement, but possiblement.
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