… is from page 453 of Deirdre McCloskey’s lovely 2006 volume, The Bourgeois Virtues :
Americans have a great deal. They have a great deal, I said, because they produce a great deal. Contrary to your grandmother’s dictum – “Eat your spinach: think of the starving children in China” – consuming less in rich America would add nothing to the goods available in China. Not a grain of rice. Countries are rich or poor, have a great deal to consume or very little, mainly because they work well or badly, not because some outsider is adding to or stealing from a God-given endowment. To think otherwise is to suppose that goods come literally and directly from God, like manna. They do not. We humans make them.
For evidence that the belief that wealth is a fixed stock of stuff – for evidence that zero-sum economic thinking remains a prominent curse – see the Economic Policy Institute e-mail highlighted in this recent post by Greg Mankiw . Mankiw is correct to suggest that the kinds of economic misunderstanding and ignorance suffered by the great majority of people have almost nothing to do with their failure to grasp the important points of high-level economic theory. Instead, those misunderstandings and ignorance are nearly all of matters that are (or ought to be) covered in a first-semester introductory course in microeconomics – matters such as the ubiquity of opportunity costs (“TANSTAAFL “); the reality of mutual gains from voluntary trade; the fact that wealth is not fixed in amount; the importance of understanding that costs (for example, exports) are not in themselves benefits.
I submit that the marginal value to the world today of a first-rate modern-day Frederic Bastiat  would be vastly higher than would be the marginal value of a first-rate modern-day Paul Samuelson .