When people make decisions about health—their own or the public’s—they’re not thinking rationally, and that’s a very good thing.
Of course the world doesn’t work this way.
A huge literature in psychology, sociology, and (at last) economics now recognizes that the rational choice model is bunk. So what’s the alternative? Multi-Level Theory is the idea that people have cognitive habits — reliable ways of thinking — that provide easy paths to the best actions for themselves. But these cognitive habits can be influenced by others, who may or may not have their best interests in mind. The video below explains multi-level theory in way that may be intuitive.