Comment: Quick question

(See in situ)

Quick question

Often I'll go to a post to just check it out, but then come back when I have more time to read the whole thing or leave a comment, and sometimes I can't remember if I've already upvoted it. I'm then afraid to up-vote it and "be guilty" of trying to vote twice. But sometimes I *will* go to upvote something and it won't work, and I wonder if it's because maybe I already did and we're somehow actually prevented from voting twice. I have certainly never knowingly voted for a post or comment twice.

So my question is: if we do vote on a post, are we prevented from voting on it again?

When we try to pick out anything by itself, we find it hitched to everything else in the Universe.
~ John Muir