Economists gave real families a guaranteed income in 1968 — work barely dropped

The New Jersey Income Maintenance Experiment, the first large randomized trial of a negative income tax, gave over 1,300 low-income families a guaranteed cash floor for three years starting in 1968. Critics predicted recipients would quit their jobs en masse; the actual drop in measured work hours was small.

— Wikipedia contributors, Negative income tax — New Jersey Income Maintenance Experiment, 1968-1972