[SaintessHeart]

Originally Posted by JokerD

There is no correlation between IQ and common sense

Actually, there is no such thing as common sense. As GrimaH from HWZ-SG aptly put it :

Unfortunately, there simply isn't a common-sense answer for many questions. In politics, for example, there are a lot of issues where people disagree. Each side thinks that their answer is common sense. Clearly, some of these people are wrong.

The reason they are wrong is because common sense depends on the context, knowledge and experience of the observer. That is why instruction manuals will often have paragraphs like these:

When boating, use common sense. Have one life preserver for each person in the boat.

When towing a water skier, use common sense. Have one person watching the skier at all times.

If the ideas are so obvious, then why the second sentence? Why do they have to spell it out? The answer is that "use common sense" actually meant "pay attention, I am about to tell you something that inexperienced people often get wrong."

Science has discovered a lot of situations which are far more unfamiliar than water skiing. Not surprisingly, beginners find that much of it violates their common sense. For example, many people can't imagine how a mountain range would form. But in fact anyone can take good GPS equipment to the Himalayas, and measure for themselves that those mountains are rising today.