There is always something that goes against common knowledge.
Your examples for instance- What about shower Radios? Watch that 'lectricity!
Humor aside, my point is still has some validity in it, as far as the common part goes. If common sense is just drawing an inference from common knowledge, where do we draw the line on what is common knowledge. It would seem to me that only the person that does something apparently stupid actually knows if they possess common sense or not.
If a guy takes the oil plug out of his car while underneath it, that would seem pretty stupid. Yet it can be considered a common error in people that have never changed oil before and don’t know what to do.
The label of not having common sense is applied willie nilly and without consideration all the time. Which still makes it useless because common usage has warped it into exactly what my OP is talking about. Your definiton is a great model, and I agree with it. Now we either need to the whole world to realize it, or just drop the whole silly idea. Personally I wouldn’t say somebody that burns themselves because they were trying to Iron clothes they were wearing lacks common sense- I would just call the f’in stupid. YMMV
I have the feeling though that this whole common sense thing will just continue and go the way of the Schizophrenia defintion. (you know those Idiots that think it is multiple personality disorder)