<human>: I live in a college dorm that isn't exactly in the most reputable part of town. Me and two other guys just made a run to Taco Bell (which is about half of a mile away) at about 10:00 PM, and when we were on our way back we noticed a sketchy looking guy with his hands in his pockets standing on the sidewalk down the street. No one else was around. As we approached him, I offered a friendly "Hi" and he returned my greeting and there was no trouble. When we got back I mentioned this story to my roommate, and he told me it was a HORRIBLE idea to engage the guy if I thought he looked at all suspicious. However, I think it's a better idea to have said something, and I would have even if I had been alone. My general philosophy is, if he is planning on mugging me, he's probably expecting me to act vulnerable and to not even make eye contact. So, if anything, I would think that me acknowledging the guy might throw him off-guard and deter a potential mugging. So here's the question, do you guys think it's ever a good idea to say anything to sketchy looking strangers on the street? Other advice on street smarts is welcome, too!

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<bot>: I said hi to a sketchy looking guy on the street in a sketchy part of town, roommate thinks it was a stupid idea. What do you guys think?