Bryan Caplan  

Hanson's Mistake: Facts, Values, and Experts

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Robin Hanson begins his health econ class with a heavy dose of disillusion:

I teach Health Economics starting today, and every year I start with data assuring students that learning data will not change their health policy opinions.

He cites a number of studies purportedly showing little relationship between experts' positive and normative views, and concludes:
While most economists think that the facts they spend years studying influence their policy positions, most policy opinions are apparently determined almost entirely by values. Since it is obvious that facts are very relevant, this all makes me ashamed to be ... human.

Robin and I discussed this over lunch. It turns out that his summary of the literature is at best misleading. By Robin's own admission, many studies DO find the expected correlation between expert's (and non-experts!) beliefs about how the world works and their beliefs about what policies we should have. Robin is actually making the subtler point that after controlling for core values, positive beliefs do not have any additional ability to predict policy views.

The upshot: It's quite possible that Robin will change his student's policy views after all. But if he does, he will probably change their values in the process. If this seems unlikely, consider: Can studying health economics undermine the value judgment that "You shouldn't put a price on human life?" In my experience, it can and does.

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COMMENTS (4 to date)
Daniel Klein writes:

Nice post. The distinction between "values" and "positive beliefs" is much less substantive than people suppose. Within one conversation, certain beliefs are on the table, and then there are background beliefs or opinions, called "values." But if you open up the larger, higher, deeper conversation, then the "values" are on the table and they become "postive beliefs" at that level; those beliefs are often about moral sentiments, but they are "positive" nonetheless.

The important distincion is between different levels of belief and conversation, not between "positive belief" and "values."

Bryan is right: Eduation can affect belief and opinion at the larger/higher/deeper level.

eric writes:

Robin's way too optimistic. Take this to its logical extreme. Tell them that, objectively, they will fail to be successful at whatever they do. Most journalists, academics, city council members, are hacks, barely 1/10 as good as their betters. Most marriages fail, most people not fully self-actualized, most people way overconfident in their ability to dance, communicate, invest, or drive. Most businesses fail, most new ideas and songs are bad. Most people won't be the high school quarterback, or the head cheerleader. In sum, expect to fail at everything most important to you.

Turn on, tune in, and drop out! Why not just hook up to sensual delights, get something out of this meaningless, futile existence?

John T. Kennedy writes:


"In my experience, it can and does."

Do you mean you modify your own values in light of facts, or that that you experience success in getting others to modify their values upon presenting them with facts?

ghwcu writes:

I think that all people both intelligent and unintelligent in some way or another have their on set of values determine their decision making. I am unsure of what grade level Robin Hanson teaches, but i do know that young or ignorant people (not stupid) definitely allow their values to take control of their ideals. Intelligent people, or well educated people on the other hand still allow their values to affect their decision making even if unconsciously, as Leopold so often alluded to in his novel Sand County Almanac. But intelligent people also allow their values to be manipulated, questioned, and evolved through learning.

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