Let me start by being perfectly clear that we should always employ reasoning when it comes to making decisions that matter. However, an important part of the reasoning process is knowing when to defer to those who know more than you on a particular issue, especially when "common sense" is anything but common, and often in conflict with reality. Further, personal freedoms to reject the scientific consensus on certain issues can have a devastating impact on others. For these reasons and more, understanding the full answer to this question is extremely important.
What is generally referred to as "common sense" is a subjective sense of our own knowledge. In psychology, there is a phenomenon known as the Dunning-Kruger Effect, which is the illusion that we are smarter than we actually are based on the fact we lack the cognitive capacity to realize our own ineptitude. In fact, this is only one of the hundreds of known cognitive biases that virtually assure that our perception of reality is greatly skewed and often incorrect.
From an evolutionary perspective, these biases are a result of helping us pass on our genes. Evolution does not care if we are smart, logical, reasonable, rational, or even right—as long as our intuitions and "common sense" are more conducive to passing on our genes than they are hindrance to that goal. The accurate information we do have as a result of the non-conscious and non-deliberate processes is obtained partly by genetics and partly by our environment. For example, it is "common sense" that we don't want to jump off a cliff because our ancestors had a healthy fear of doing so... that is why they lived long enough to pass on their genes. It is "common sense" for us to look both ways before crossing a road not because of our primate ancestors, but because of learning in our current environment. Be careful not to associate all evolutionary tendencies with good common sense. For example, eating as much as you can at every opportunity might have helped our ancestors survive, but this tendency is sending us to our graves early.
Here are just some examples where "common sense," "gut-feelings," "intuitions," and "our own understanding" are clearly at odds with reality:
It would be nice if we can just "know" things magically. In fact, the appeal to common sense is often based on a combination of laziness and a defense of our own intellectual limitations. The pain of not knowing something is reduced by simply thinking we know—and not just know but know better than those who spend their lives doing the work to really find out.
There is a clear relationship between ignoring the claims of experts in favor of your own "common sense" and trust. If we were to undergo brain surgery, very few of us would question the surgeon's technique and choice of surgical instruments. Why? Our level of trust in the surgeon is high, and our level of confidence in our own understanding of the topic is very low. But what if the Internet was full of websites claiming that brain surgery was a conspiracy, and just a surgeon's way of separating you from your money. No matter how full of crap these sites were, you may be persuaded by their strong emotional appeals, anecdotes, and cherry-picked data. You would be under the illusion that your level of "knowledge" on the topic is strong, and conversely, your level of trust in the surgeon would drop, to your own, and often society's detriment.
Here are some things to keep in mind to prevent this intellectually dangerous downward spiral.
Discussing freedom is a touchy issue, but it is important in understanding that your "right" to reject certain findings in science is limited, just as your "right" to freedom of speech is limited by not yelling "bomb" in an airport. Some examples include:
Reason: Book I - A Critical Thinking-, Reason-, and Science-based Approach to Issues That Matter is based on the first two years of The Dr. Bo Show, where Bo takes a critical thinking-, reason-, and science-based approach to issues that matter with the goal of educating and entertaining. Every chapter in the book explores a different aspect of reason by using a real-world issue or example.
Get the book, Reason: Book I - A Critical Thinking-, Reason-, and Science-based Approach to Issues That Matter by Bo Bennett, PhD by selecting one of the following options:
Enroll in the Daily Doses of Reason Online Course. This is passive course where you are sent one lesson per day by e-mail. There is no required interactivity. Each lesson averages just a few minutes.
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