not to be too cynical here, but I would say that the most-apt description of the rationalists is that they are people who would say they are constantly looking for updates to their models. But that they are not necessarily doing it appreciably more than anyone else is. They will do it freely on unimportant things---they tend to be smart people who view the world intellectually and so they are free to toss or keep factual beliefs about things, of which they have many, with little fanfare, and sure, they get points for that. But they are as rooted in their moral beliefs as anybody else is. Maybe more than other people since they have such a strong intellectual edifice that justifies not changing their minds, because they believe that their beliefs follow from nearly irrefutable calculations.