If you want to feel like the smartest person in the room, often a good way to accomplish this is to be the only economist. Frequently, the one economist will say things that make a lot of sense that no one else would ever come up with. When I am that one economist, I sometimes feel like a genius. Until a second economist enters the room, that is. Because when the second economist shows up, he or she often says all the smart things I was going to say, before I can say them. It turns out, it is not the economist who is brilliant, but rather the training we get as economists which leads us to think differently from non-economists, that sometimes makes us seem smart.
It is true that economists generally think more deeply than most people. They are used to considering tradeoffs and long-term effects of a given policy or decision, which is something that eludes most people.
However, the mindset espoused by Steven Levitt is quite dangerous, and speaks to a tendency towards arrogance that is often seen among economists. Because they are generally wiser and smarter than other people, many economists begin to think that they are absolutely smart and wise. This in turn leads them to rely too much on their own perceived genius, which is why economists generally don’t have an issue with some form of central planning: they really think that they are smart enough to plan an economy.
They are wrong, of course, because they lack one essential ingredient: knowledge. While economists may be pretty smart, and even wise, they simply do not know enough to manage an economy properly. And so, they get so caught up in their brilliance that they never realize they are astonishingly ignorant.
It is good to be able to think through issues, and it is true that many economists do that, but you are right that often economists give themselves far too much credit for being smarter and wiser and more knowledgeable than they really are.