YouNotSneaky! is very wise, judging from his "12" commandments for and about economists:
1. The answer to most questions in economics is usually “It depends”.
2. People respond to incentives, but incentives are determined in their own head and who knows what goes on in there.
3. But on average, masses of people respond in fairly predictable ways and these predictable ways, embodied in the so-called “Econ 101” thinking, are pretty useful guides. They are not absolutes however.
4. “On one hand … on the other hand” is about as good as you can do in a complicated world.
5. All economic models boil down to two (occasionally three) curves on a blackboard that cross. If it’s more than that or if you can't draw it that way, then your model stinks.
6. First Fundamental Theorem of Economics: Where the two curves cross, it’s important.
7. Game theory accidentally teaches us that outcomes are very sensitive to the structure of interaction. Small changes in the rules of the game can produce vastly different outcomes.
8. A logical, aesthetically compelling, story is important, even if the assumptions are crazy. Check it with math.
9. Anyone who makes exaggerated claims about their pet theories, ideas, or solutions, be they mainstream or heterodox, either doesn’t know what they’re talking about, hasn’t done their homework or is trying to sell you something (it could also be the case that their ego is well over blown, because, perhaps, maybe, I'm just guessin', their father was famous and worked for some famous politician or something). “Our results SUGGEST…” is a good indicator that a person has thought hard about their subject. At least as far as these things go. A thorough method combined with some humility should invite more attention than extraordinary claims of genius. Scientific progress takes place at the margin.
10. When an economic idea about how things work pops into your head, your very next question should be “why is that wrong?”. It’s useful to simulate competition among ideas in your brains so that only the truly good ones survive. Success, however, is not guaranteed.
13. “I don’t know” is often the best answer that can be given.
(even if he cannot count, thereby showing that NotSneaky often overlooks his own admonishment about checking the math!)
Let me add a few of my own to make it a (real) round number:
12. People everywhere are pretty much the same. It is the incentives and constraints they face that differ.
13. Everything that an economist says today has been said before, typically in more elegant fashion, by an economist of an older generation. That makes them neither true nor false. It just suggests that what is new in our profession is the technique, not the insight.
14. Beware when economists start to talk using metaphors ("shock therapy," "diagnostics," "big push" to use some recent ones from this blog). It is a good sign that they do not quite know what they are talking about.
15. When economists disagree about policy, it is most often because of implicit moral and political judgments, rather than economics per se.