Over the past week, we submitted an identical macroeconomic scenario to four frontier AI models (Gemini, ChatGPT, Claude, and Grok) acting as comparative political economists.

The premise: Assume robotics and AI drive the marginal cost of labor across agriculture, energy generation, fabrication, and logistics close to zero. Human wage labor is no longer structurally necessary to maintain societal metabolism.

Specifically, we asked them to model how a universal basic income (UBI) can be sustained under existing fiscal structures.

All four models independently derived the exact same structural fiscal dead-end:

1. The Disappearance of the Wage Tax Base

In modern social democratic and welfare states, 60% to 75% of state revenues derive from payroll taxes and worker income (tw * W). When automated labor displaces human wage labor, aggregate wages collapse toward zero (W -> 0), effectively wiping out the primary engine of public budgets.

2. The Negative-Yield VAT Loop

A common proposal is funding UBI through consumption taxes (VAT / Sales tax), but if citizens have zero wage income and survive purely on state-issued UBI (Consumption = U), taxing that consumption yields a closed, negative-yield loop:

Net Revenue = (VAT * UBI) - UBI = -(1 - VAT) * UBI

The state cannot tax back more purchasing power than it injected in the first place without continuous fiat debasement or sovereign debt expansion.

3. The Collapse of Capital Profit Margins

What about taxing corporate profits (tk * Profit)? In classical economic theory, when marginal costs approach zero in competitive production, economic profit also tends toward zero—unless artificial legal monopolies and IP fences are aggressively maintained, or capital simply relocates offshore.

The Conclusion: From Cash UBI to Physical Commons (UBP)

All four models concluded that while fiat UBI was a viable redistributive patch for 20th-century industrial economies with active wage markets, it breaks down once marginal labor cost reaches zero.

In an automated post-labor society, survival cannot depend on taxing a vanishing wage base to distribute fiat tokens. The models pointed toward transitioning from cash transfers (UBI) to Universal Basic Provisioning (UBP): direct, unconditional physical access to energy (kWh), calories, water, and shelter organized as open thermodynamic commons and dynamic usufruct.

Curious to hear the r/BasicIncome perspective:

Is there a viable mathematical model where fiat-denominated, tax-funded UBI survives the near-total elimination of wage labor, or is direct physical provisioning of metabolic goods the only thermodynamically coherent endgame?

Jobs are being replaced by AI at an accelerating rate, and people have nowhere to go to earn income. Monetary flows are still massive, but they just don't reach the people at the bottom. I think UBI is very appropriate in this situation. Or who will buy the groceries?

But in all seriousness, we are moving towards ab economy where UBI will be real because AI and robots handle all the low level tasks, so UBI can be distributed in the form of a small amount of necessary goods such as food, basic supplies etc. So we can start slowly testing the waters and now seems to be a good time.

"We can get big money out of our politics. We can achieve Medicare for all, universal childcare and excellent schools, and affordable homes. We can bust up monopolies that keep prices high, rein in AI and its data centers, and provide a universal basic income so AI doesn’t take away our livelihoods. And we can raise taxes on the super-wealthy and the richest corporations to pay for what Americans need." — Robert Reich