Harvard economist Greg Mankiw is notorious for trying to justify the income of the very rich on the grounds that it's what they deserve. In this column, for example, he uses the example of Steve Jobs as a person who deserves his wealth, having been in charge of a company that built some hugely popular electronic devices. The idea is plausible at first blush: Jobs' products are indeed very popular.
But it quickly runs into enormous problems. This "just deserts" way of looking at the world is perennially tempting for conservatives — the flip side being that poorer people also deserve what they get — but they will have to do better than this to justify and valorize the existing social structure.
Consider the case of economic growth. As Matt Bruenig points out, the mysterious "Solow residual" — the source of productivity that can't be directly attributed to capital, labor, or land — almost certainly consists at least in part of knowledge, which has been piling up for centuries:
If we are being good "just desert" adherents, then we need to divorce out the massive chunk of the total output that constitutes the Solow residual and ensure it makes it to its rightful contributor. All of our national product attributable to the world's accumulated knowledge of algebra — which includes much of Mankiw's work it should be noted — rightfully belongs to ancient Babylonians, ancient Greeks, and a whole host of other long-dead historical figures. All of our national product attributable to electricity technology rightly belongs, not to anyone living, but to people like Nikola Tesla and Thomas Edison. In short, the view that individuals should receive only their marginal product actually generates the conclusion that the substantial part of our national product resulting from inherited technology and knowledge belongs to no living person, or more reasonably to everyone in general. [Demos]
Even that isn't going far enough! As Thomas Kuhn demonstrated in the Structure of Scientific Revolutions, nearly all major scientific breakthroughs were made by multiple people simultaneously and independently, and were critically dependent on certain background conditions in society. In other words, if we could somehow figure out how much of economic output stems from the discovery of calculus, even Newton would not deserve full credit for it.
We can take it even further: What about the English language itself? That is to say, practically every single economic activity depends on a foundation of literacy that has been built into society. No business today can operate without a functional language as a bedrock condition. That is quite obviously the result of thousands of years of communal creation and evolution. Today's Job Creators can't possibly claim to have "built that," and the very idea of trying to single out individuals in the creation of English is ridiculous on its face, with the possible exceptions of Shakespeare or William Tyndale.
Finally, merest existence means being ensnared in a web of obligation that it would be futile to map out. Every person alive is built at great effort and pain from the flesh and blood of another person: your mother. How could one possibly begin to even "repay" such a debt? Presumably, she deserves all of your income less what it takes to keep you alive, since she is literally responsible for your creation. But that's not even the end — before your mother, there was her mother, and so on, in an unbroken chain of life creating life stretching 3.6 billion years back to the primordial sea. Remove just one of the links, and you wouldn't exist.
Anyway, one could continue in this vein, but I'll leave it there. In my view, the sheer impossibility of ever allocating desert in any sort of systematic or consistent way means we should guarantee a minimum of safety and security for every person. But at a minimum, Mankiw and his fellow 1 percent apologists would do well to abandon this line of reasoning.