http://www.amazon.com/Murphys-Law-Book-Two-Reasons/dp/B00123...
... and its author is a guy who won a contest to come up with successors to Murphy's Law. Backstory here:
http://www.statusq.org/archives/2001/11/26/ http://www.statusq.org/archives/2001/12/04/
A very similar line occurs in a Robert Heinlein story.
Edit: Googling around, I ran across the following quote from a German general which was cited as an antecedent to the above. While it only vaguely resembles that idea, it is a marvelous specimen of that distinct microgenre, witty aphorisms by dudes from European military history:
I divide my officers into four classes; the clever, the lazy, the industrious, and the stupid. Each officer possesses at least two of these qualities. Those who are clever and industrious are fitted for the highest staff appointments. Use can be made of those who are stupid and lazy. The man who is clever and lazy however is for the very highest command; he has the temperament and nerves to deal with all situations. But whoever is stupid and industrious is a menace and must be removed immediately!
Isn't that great?