I don’t think Eliezer’s wording necessarily implies “probability 1”. I occasionally say that thing X is impossible, meaning that the probability of not-X is close-but-not-quite 1. I don’t specifically say that I don’t mean probability 1 exactly, because it should go without saying that nothing has probability 1, and I can’t be bothered with tacking on the extra words.
I don’t think Eliezer’s wording necessarily implies “probability 1”. I occasionally say that thing X is impossible, meaning that the probability of not-X is close-but-not-quite 1. I don’t specifically say that I don’t mean probability 1 exactly, because it should go without saying that nothing has probability 1, and I can’t be bothered with tacking on the extra words.
It’d be nice if things like that indeed did go without saying, especially on this site.