Mr. Zwolinski’s basic income guarantee is essentially the negative income tax advocated in the 1950s by Milton Friedman, who won the Nobel in economic science in 1976. Every person would receive a cash grant from the government, irrespective of income or employment status. Other sources of income would be taxed as usual, so that people with moderate to high incomes would still be net taxpayers. Friedman advocated a grant just above the poverty threshold, currently about $25,000 a year for a family of four.

One stumbling block is that such a payment would enable large groups to pool their resources and live very comfortably at taxpayer expense. For example, a group of 10 families could form a commune and supplement their $250,000 in cash grants with the untaxed fruits of gardening and animal husbandry. In some states, they could also grow marijuana legally, both for sale and personal consumption. Days would be free for sipping lattes and debating politics and the arts, or for practicing their guitars, reading novels, writing poetry or skinny-dipping in the pond.

The number of people forsaking paid employment in favor of lives like these might be small, but there would inevitably be some. And it would be only a matter of time before reveling commune members became a staple on the nightly news and social media. So despite its admirable simplicity, an income grant large enough to lift urban families from poverty would be politically unsustainable.

A smaller cash grant could still be an important policy tool, but we would need some way to supplement it without undercutting work incentives. One possibility would be to combine it with an open offer to pay subminimum wages for the performance of useful tasks in the public sphere.

Previous expansions of the nation’s infrastructure — such as the Works Progress Administration during the Great Depression and the Interstate Highway System initiative of the 1950s — have identified many useful tasks that could be done by properly supervised unskilled workers. Together, the earnings from such jobs plus the small basic income grant would exceed the poverty threshold.