I think that I have common sense, but sometimes (well, often, actually) it fails to show up on cue. If I were taking a test with short answer or essay questions, and I was given a hypothetical scenario, and asked what the logical/ sensible course of action would be in that situation, I would most likely give the correct answer. Even if this question came up in an interview, and I had to give my answer verbally, the odds would be in favor of my answering correctly. However, when I'm actually in the moment, dealing with an actual situation, there's a significant chance that the sensible course of action won't come to me on time. Thus, my behavior in said situation will make it seem like I lack common sense, and that's what any observers are likely to think. If I have a chance to think about this sort of situation after the fact, the sensible course of action is generally painfully obvious.
I'm not sure exactly why this is the case. It could have to do with the fact that my verbal IQ is *much* higher than my performance IQ. I know that when I have the chance to sit down and think/ reflect/ write/ talk about something, my thinking is generally much clearer than it is when I'm out there doing. This could also have to do with the fact that I tend to overfocus on one or two details of a task or situation, and overlook all other crucial details.
Of course, to anyone who doesn't live in my head, none of these things are apparent, and I just appear to lack common sense. *shrugs*
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"And I find it kind of funny, I find it kind of sad./ The dreams in which I'm dying are the best I've ever had."