It's one of those things where there is clearly some sort of truth in what he says, but where it really only amounts to a tiny part of the whole truth. It's far too simple, because the dichotomy that he describes is only a lazy sketch of the real situation, which is that most people fall in between. It's a psychological interpretation of a media myth. He pays lip service to the fact that people have each type of mentality within them, but there are more than two ways of looking at the world to begin with. He also makes little account of the fact that social conservatives and economic conservatives actually disagree horribly as often as not on certain points. Nevertheless, I think that the primary point - that different systems of belief arise because of different moral assumptions - is spot on.

On the other hand I think that what is as interesting as anything else is his tendency, which he doesn't seem to notice, to classify everything into discrete little boxes. Not just the main division, but his assertion that there are precisely six different kinds of liberal. We see the same thing with self-help books that describe, say, six types of office colleagues that you have to deal with (my parents have that one). People like to put things into little boxes, and in doing so they distort the true nature of what they describe. I just wonder if the very tendency that this guy displays here isn't the same tendency that has seen the division between conservatives and liberals whipped up to such an extenst in the first place, thereby allowing him, ironically, to come up with his little theory about how everyone exists in little boxes.