There is no such thing as common sense. When I attended college, several decades ago, I was required to take a course in law, somehow connected to business. I was delighted at the prospect because I had only one experience with a lawyer before, which concerned research for a patent that I applied for when I was a teenager. The course was built around cases that had already been tried and conclusions reached. We students were given the “facts” and based on testimony and evidence given at the trial or hearing, independently, we were to reach a conclusion. Of course, we did not know the real outcome before we studied the case; we were graded on our results as compared to the “official” court decision. If we happened to reach the same conclusion as the judge, we were golden, but if we reached another outcome, we were ridiculed or something worse – we got a “D” grade.
As it turned out initially, I naively based my decisions on what I thought were principles of justice, fairness, righteousness, logic, ethics, and common sense. During the first half of the semester, I was striking out more often than not. My good grades or correct decisions looked more as if they came from the flip of a coin, rather than the principles I learned as a child. I argued to no avail; I was really out in left field with my idealistic upbringing. After all, some judge had made the real-world decisions long ago, but as far as I was concerned, there were many more innocent people in jail than were thugs.
What to do? Stick to my principles, or change my attitudes about law and the pursuit of happiness and try to pass the course? Since I had a good grade-point average and I was in my sophomore year, I opted for the latter-- happiness. So like any smart engineering student, I used my same defective techniques to reach a conclusion, and after I was completely satisfied that I had made the right decision, I reversed my decision on the paper that I turned in to be graded. Guess what? My grades got much better-- yeah, almost perfect! I was not happy about the method I needed to pass the course, but, hey, it worked!
So much for justice, ethics, and common sense. Thank goodness, we engineers, scientists, and technologists don’t use “lawyer techniques” to solve our science and engineering problems… or do we? What about global warming? Where is the evidence? What about carbon footprints? Where is the evidence? What about evolution? Where is the evidence? What about coal and oil reserves? Where is the evidence? What about the 911 conspiracies? Where is the evidence? What about gun control? Where is the evidence? Try using your definition of common sense on these issues to reach a conclusion, regardless of the side you take. See? It doesn’t work.