Many economists forget that the first-order problem of an aging society, one with high life expectancy and low fertility, is how to redistribute income from workers to retirees. How fast output grows is, surprisingly enough, the lesser question. If you have roughly as many retirees as workers, what each worker produces must be split in two, one part for the worker, one part for the retiree. At a basic level, it does not matter whether we do it through taxes, as in a pay-as-you-go social security system, or through capital income, as in a fully funded one. Workers will not be happy to see half of their income taken away, whatever the absolute level of that income. This redistribution will poison the political system and lead, with high probability, to dysfunctional policies. We are already seeing it across Europe in the fights over retirement benefits. And much of the American unhappiness about the profits of large corporations, largely owned by the old, is the same conflict, only in the fetishized form of equity ownership. Claims of the form “technological progress (e.g., advances in AI) will fix the problems brought by aging” miss the political economy of the situation. Aging is about politics, not TFP.