Julian Sanchez writes:

I'm always a little puzzled by a rhetorical strategy I occasionally encounter in friendly political arguments. I'll often, unsurprisingly enough, end up taking a libertarian position, and midway through the back-and-forth, my interlocutor will respond with something like: "Well, you're a libertarian, so of course you think that, but..." as if to suggest that an ideology is some kind of suspect ulterior motive, along the lines of "Well, you work for ADM, so of course you're for ethanol subsidies." But of course, that's sort of backwards: I don't believe in low taxes, strong property rights, free trade, and robust civil liberties because I'm a libertarian. Rather, I'm a libertarian because I believe all those things for other independent reasons. (And the "because" here is constitutive, not causal--being a libertarian, in other words, just means believing those other things.) It's as though once you can slap a label on a view, you've banished it, in the way we used to think knowing the true magical names of evil spirits gave us power over them.

I think the best way to rationalize the use of this rhetorical device is to understand it as a means of located at what level of abstraction the debate is proceeding. You might have been assuming that you and your interlocutor had some shared premise, and you simply didn't understand how he could fail to see that your conclusion followed from the premise in question. But then you realize that you're disagreeing because he's a libertarian and doesn't agree with your background premise. You may then think that the dispute about the background premise isn't really worth having and say, "well, you're a libertarian, so of course that's what you think" secure in the knowledge that you're not missing some key step in the argument. Since any given casual conversation is probably not a good moment to decide that your entire ideology is wrong and you should be a libertarian, there's really nothing more to say, and you walk away sure that you're right.

The same kind of dynamic in reverse is why an article called "The Liberal Case Against The Minimum Wage" or "The Conservative Case for Gay Marriage" or "The Libertarian Case for Universal Health Care" would be more interesting interesting than the converse ones. "The Libertarian Case Against The Minimum Wage" and "The Liberal Case for Universal Health Care" are both pretty banal, and probably cover well-ploughed territory. People who aren't libertarians (in the first case) or liberals (in the second case) are going to feel that the author can just be ignored. He's a liberal so of course he thinks there should be universal health care, but I'm not a liberal so why should I care what he thinks about this.

The difference here is that Julian seems to think that he's come to various libertarian conclusions each on independent grounds and that it's just a kind of coincidence that when you add all these conclusions up what you get is libertarianism. I think a more realistic picture of people's political ideas (people who think a lot about political ideas, that is, other people probably have a very different belief structure) is that a small number of background beliefs about matters moral and empirical are driving their conclusions on various subjects. Correctly identifying those beliefs can be crucial in helping to understand what's going on.