"Self-sufficiency is the road to poverty."
This idea is from Russell Roberts, an economist who blogs at Cafe Hayek.
At first I found this idea to be incorrect, as I prize self-sufficiency. However after just reading a small portion of Roberts' argument I see the truth in the statement. Wealth is a product of specialization and the division of labor; being able to trade with others.
Even though I see the truth in the idea, I am still trying to think what role self-sufficiency should play in my life. There is an amount of satisfaction that comes in being self-sufficient, but I think this is an attitude only held by those who are privileged with enough leisure that self-sufficiency is a choice rather than a necessity.