For me it’s this: From a pragmatics perspective “the rational way to buy a car is...” repeats information—when a person shares a method of doing something everyone assumes the speaker thinks that method is rational. Repeating it is redundant and redundant speech acts have a tendency to come off as arrogant and squicky. It’s what you do when you talk down to someone.
It’s also just sloppy to use words with connotations that don’t apply when a better word exists. “Rational” connotes some general discussion of cognitive algorithms.
So I suspect it’s a combination of a)sloppiness is bad and b)sloppiness looks and sounds bad
But then what about “optimal car-buying”? Surely if someone is taking the time to describe how to buy a car, they probably think it’s the optimal method, or at least as close as they can get. So “optimal” would seem to be redundant too, and yet we would seem to prefer one over the other, even though they basically mean the same thing thing in this context.
Now, there may be some arrogance built into “rational” that’s not present in “optimal,” but I don’t see the issue as one of redundancy. Rather, it seems like “rational” can sometimes come off as an assertion of superiority over another—i.e., something like a man telling a female colleague that she needs to be more rational.
For me it’s this: From a pragmatics perspective “the rational way to buy a car is...” repeats information—when a person shares a method of doing something everyone assumes the speaker thinks that method is rational. Repeating it is redundant and redundant speech acts have a tendency to come off as arrogant and squicky. It’s what you do when you talk down to someone.
It’s also just sloppy to use words with connotations that don’t apply when a better word exists. “Rational” connotes some general discussion of cognitive algorithms.
So I suspect it’s a combination of a)sloppiness is bad and b)sloppiness looks and sounds bad
But then what about “optimal car-buying”? Surely if someone is taking the time to describe how to buy a car, they probably think it’s the optimal method, or at least as close as they can get. So “optimal” would seem to be redundant too, and yet we would seem to prefer one over the other, even though they basically mean the same thing thing in this context.
Now, there may be some arrogance built into “rational” that’s not present in “optimal,” but I don’t see the issue as one of redundancy. Rather, it seems like “rational” can sometimes come off as an assertion of superiority over another—i.e., something like a man telling a female colleague that she needs to be more rational.
Something that is not optimal is merely ‘suboptimal’ whereas something that is not rational is irrational.
Things that are not rational can also be be arational. Most obviously terminal values.
More precisely indicates we want to optimise a decision over a particular utility function, or at least set of desires.