Many people seem to believe that “common sense” will solve all the world’s problems if people would just use it more. They post about it, talk to their friends about it, they shake their heads and politic. But left to common sense, Humanity would not have achieved many of the wonderful advances we have made over the centuries.

Look at birds. They are small, light, and feather-winged. Common sense tells us that humans cannot fly.

Look at the moon. A distant object hundreds of thousands of miles above us. Common sense tells us that we cannot walk on it.

Look at any celestial body, in fact—sun, stars, retrograding planets. What possible clues to the physics and histories of such far flung entities does common sense provide?


The answer: Not much. Common sense is not a great tool for making progress; it is a good tool for surviving. That’s where it comes from after all. Our mammoth-hunting ancestors who ignored the rustling bushes or assumed it was the wind were eaten when the giant sabertooth emerged; it became common sense to assume an individual—especially a dangerous creature—was behind the noise. A malicious mind behind the unknown.

It was a great tool for a long time. But common sense does not tell us anything about airfoils, combustion, or cosmology. No, these types of knowledge require something more. They require curiosity. They require someone brave enough to point his spear at the tall grass and advance, ready for anything. At times, it was a killer feline on its evening prowl. At others, it hinted at a mechanism of reality in the pattern of wind rushing through the valley as the sun set and the air cooled on the eastern slopes.

These realizations also require data. They require in-depth investigations and drawings of the curvature of avian wings, repeated observation of materials that are susceptible to heat and flame with explosive results, numerous calculations and models regarding the behavior of heavenly bodies. It takes teamwork and mulish determination to understand what’s taking place behind the scenes. It takes a rejection of appearances to instead ask, “Why? How can that be?” When common sense gives a simple answer, inquisitiveness tries to find what is really going on, and it’s very rarely simple.

While calling something “common” is usually to say that it is simple, found frequently, or shared widely, an alternate definition as worded by Merriam-Webster is one I feel more befits the word when used in this term: “falling below ordinary standards; lacking refinement.” In this sense, common sense is all too common… it provides a basic conclusion to a situation without helping really understanding the breadth and depth of what is going on. It is often contrary to reality, and ignoring the facts found through a thorough investigation in preference of “common sense” does far more harm than good.


Applying common sense to illegal immigration from Mexico, for instance, would reasonably bring one to the conclusion that a border wall and increased militarization of the patrol forces would decrease the number of undocumented entrants. After all that’s an added deterrent, a tougher obstacle. But this an issue for which there are many years of verifiable data—and it tells a different story. According to Douglas Massey, professor of sociology at Princeton who has been tracking and analyzing this dynamic for decades, the periods of strictest control along the Mexican-US border have been years of the greatest net illegal immigration (inflow is greater than outflow). In more relaxed times Mexican men would head north to take advantage of seasonal work that many Americans didn’t like or saw as beneath them (such as picking fruit), then take the earnings home and live fairly well the rest of the year. It was a benefit for both countries as American farmers had laborers, American stores had full shelves, American citizens paid low prices, and Mexican citizens improved their own lives and those of their families.

In periods of stricter border control, however, since it took more effort to get north, Mexicans would be reluctant to head back home when the picking season was over. They went to all that work and spent all that money to get here, they didn’t want to have to do it again next year. They’d stay and become a burden on the American infrastructure—picking season ended so they had to find jobs that students and uneducated Americans often took temporarily. They were also unable to pay into civil welfare programs like Social Security that would have benefited both legal immigrants and US-born citizens.

These are easily verifiable data points that can be tracked and trended over the years. But they are certainly not common sense. They are facts, found through exploring reality, asking why, and accepting the findings even when they didn’t seem to follow the narrative being told.


In these matters and others, common sense is not the intricate tool required to discover the truth. It is a blunt instrument, capable only of applying clumsy force to rudimentary concepts.

Unless we’re ready to live in a world without space flight, without GPS or astronomy, and without strong economies, we need to be willing to use uncommon sense.