Bryan Prescot: “When all you have is a hammer, every problem looks like a nail.”
Agent Alex Marlow: “Conversely, sir, when you have a nail, you can bang at it all day with a screwdriver, a shoe or your hand and get nothing except hurt. Whereas one good blow with the hammer makes the problem go away for good.” – From Do Unto Others by Michael Z. Williamson. (Mass market paperback edition available August, 2011 from Baen Books.)