Peter Radford, at Real World Economics, writes of failed economists,
They are still teaching whatever they first thought. No amount of empirical data threatens their prestige. Why? Here’s the great scam: because economics is a self-contained, self-referential pursuit disconnected, very deliberately and carefully, from the dangers of having to be useful. It is thus immune from disproof. All that Popperian conjectures and refutations mumbo-jumbo is not applicable to economics. Economists have constructed their world so as not to have to be practical. Instead they are quasi-philosophers, quasi-mathematicians, quasi-physicists, quasi-psychologists, and quasi-sociologists. By so being they can dodge between the bullets of practical questioning and never have to improve their art. Being quasi-everything is a great defense. You can confuse all the specialists and answer to no one. Except yourself.
It occurred to me that simply by substituting “theologians” and “theology” for “economists” and “economics” one would arrive at an equally true statement. The only read difference is that it would apply to “successful” theologians even more than it does to either failed or successful economists. Historically at least, “unsuccessful” theologians either recant, are cutoff in one way or another, or form a new religion where they are by definition now successful. I guess the latter is like forming a new school of economics.
Via Mike the Mad Biologist