How much economics to learn in college?

Chris Blattman on economics as a martial art or, put differently, on the non-linear learning curve in undergraduate economics.

A longish excerpt:

My personal experience: economic theory courses are a little like karate.

After a course or two you might get your yellow belt, but basically you have just been going though the motions and learning some basics.
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Anyways, with your yellow belt, you’re a little more flexible and you have a sense whether you like the art, but if someone jumped you in an alley you would probably be worse off than before you took the class.

Your karate classes will pay off slowly, with time and practice. You might get your green or brown belt eventually, and this will serve you well in life. For most of you. For others, a little knowledge is a dangerous thing, and you will run around looking for a fight, sometimes clobbering an innocent, and basically simply miss the big picture.

Stick at it awhile longer, and you might get your black belt, some perspective and some discipline. It takes a while for this to pay off, however, and very soon diminishing returns set in, unless you happen to want to run your own dojo.

In case it’s not obvious, intro to microeconomics is the yellow belt, and intermediate micro is the green at best. An undergraduate degree in economics is a brown and an MA is arguably the black. And if you want your dojo or jedi master status then get a PhD or go into investment finance.

And of course the ass who runs around looking for a fight is the ideologically left or right jerk who manages to turn a conversation about the weather into a diatribe about free trade.

(In college I was actually just such an ideological ass–I won’t tell you what side of the spectrum but leave you to guess. Glad to say it was just a phase.)

I remember my own phase in college of being what I call an "Economics 101 libertarian". I am sure my college friends remember it too - probably less fondly than I do! It is dangerous, though amusing too, if you know what is going on. Basic micro has to be tempered both with all the caveats and exceptions that come from digging deeper within economics and with the insights provided by adjacent disciplines like sociology and psychology.

Having said that, of course, demand curves still slope down, and people still respond to incentives, and those two bits alone would do a lot to improve policy if systematically paid attention to.