Billy Foster

Ask a physicist how long it would take a bowling ball to land if you dropped it from the roof of your house. He will happily assume that your house is located in a vacuum, and then proceed to calculate the right answer. Ask an engineer to predict the path of a billiard ball after it is struck at a certain angle. He will assume that there is no such thing as friction, and the accuracy of his prediction will give him no cause for regret. Ask an economist to predict the effects of a rise in the gasoline tax. He will assume that all people are rational and give you a pretty accurate response. — Steven E. Landsburg, The Armchair Economist (1993)