While engaging self-confessed Leftists on Twitter and elsewhere, I’m less amazed than depressed that basic economics slip by. Indeed, when reading rants of naked, covetous Marxism in the New York Times Capitalists and Other Psychopaths, not once do these screeds against wealth ever consider what is easily observed by any parent with two brain cells to rub together. My nine-year-old twin grandsons have just started getting a weekly allowance. Identical