My take on common sense is a bit different. I see it as a bit more intuitive and not so much experience based. That is, some people have it, others, not so much. My mom has always said I was the one who had the most common sense out of all my siblings, whereas my sister didn't have as much. To her credit, my sister is incredibly intelligent and very book smart, so this isn't a criticism of her at all. Rather, my mom can see us both a bit more objectively than we can see each other.