it all seems like the same process to me: being more interested in the difference between two values than in the absolute magnitude of them
You can go even more general than that—this really illustrates the entire, flawed process of the way that we think. Judgment and decision making seems to take the form of “use my subconscious pattern-recognition machinery to determine what sort of situation I’m in, then make a judgment of that situation based on just a few context cues.” Manipulate the cues I rely on for judgment (such as relative magnitude), and you can manipulate the decisions I make.
You can go even more general than that—this really illustrates the entire, flawed process of the way that we think. Judgment and decision making seems to take the form of “use my subconscious pattern-recognition machinery to determine what sort of situation I’m in, then make a judgment of that situation based on just a few context cues.” Manipulate the cues I rely on for judgment (such as relative magnitude), and you can manipulate the decisions I make.