Definition of a truism from Wikipedia: “A truism is a claim that is so obvious or self-evident as to be hardly worth mentioning”.
Truisms are very attractive to the human mind because they provide simple answers to often complex human problems. While some people simply lack the intellectual capacity to think through these problems, for most of us it’s just laziness. After all, with all the shit we have to face and understand each day, it’s easy to see how simple answers can be very attractive. Hell, just trying to get a handle on my cellphone bill is a challenge, given all the complexity that vendors build-in in order to bamboozle us (see Steve’s Third Axiom: You can’t protect yourself part-time, from people committed to taking advantage of you full-time).
Truisms can have both a benevolent and a pernicious side. We often use truisms to comfort others in pain, e.g. “Don’t worry….things will get better” (they may in fact, not get better). “Everything happens for a reason” is another great comforter. But in general, truisms are pernicious because they provide answers without solutions, and usually shift the blame onto the other person. “If you want to lose weight, just eat less and exercise more” is a great one. Homeless and begging on the street? “Get a job!”. You’re a smoker? “Just quit”. You get my drift.
Truisms present a strange mathematical equation where the problem and the answer are both presented, without showing how one got to the answer. We are all familiar with Einstein’s famous E=mc². Yet few realize that the underlying mathematical reasoning to get there would fill several textbooks with the background equations. And I don’t remember sitting for any math exam where I could just show the answer without showing the actual detailed analysis (the “solution”) of how I got there. It would have been an instant “F” and a possible accusation of cheating.
And I guess that’s the gist of it: Truisms cheat us of the intellectual satisfaction that comes from doing the spade-work of solving complex problems, and smugly assign guilt to others for those problems.