In Advanced Educational Psych, I learned that, according to Piaget, children don't typically "develop" common sense until around age 14. Before that time, the brain isn't capable of comprehending sound judgment because reasoning skills are not at a point to process in that manner.
I've always considered common sense to be an intuition - an innate trait that one is born with....or without. Like the book smart vs. street smart debate. Which is better? Do people who are book smart possess common sense? Are book smart(ies) limited in the amount of knowledge because the knowledge base is strictly from a source that might or might not be biased? Or is it something that you develop from living a worldly life? Do street smart(ies) possess this trait because common sense relates to the human experience?
I'm not sure there is a right or wrong.
What I do know is as I look around, I see a lack of common sense. And I'm sure I am just as guilty. In my case, I call it a blonde moment. Luckily, those moments don't happen often. But with alot of people, I watch them attempt to reason, and it appears they can not make a sound decision, even if the answer sits before them.
Why is that? If common sense is the place where the senses come together and combine, shouldn't everyone be able to make sound judgments based on common sense? Yes, each individual has one sense that works overtime while the others do only what is asked of them, but if all senses are working, why can't people make good decisions?
Perhaps common sense is perception. Perhaps it is a combination of life experiences that meld together to formulate opinion, and once that is accomplished, then one has common sense.
I used to joke around with my children when they had a kid moment and say, 'Ah, it's ok, you haven't reached the age of common sense yet.' Ok, I admit that sometimes I still look at them, as they near or are in their 20s, and think, 'Ah, you still don't have it.' When the situation really matters, they get it, and that is what matters.
Sure, everyone is entitled to those moments when common sense escapes them. But if we are becoming a society that does not have the capability to examine a situation and formulate the "whys" and "what ifs", then what does that say about our future?