This missing fact, which Kelso had uncovered over years of intensive reading, research and thought, drastically modifies the classical paradigm which has dominated formal economics since Adam Smith. It concerns the effect of technological change on the distributive dynamics of a private property, free market economy. Technological change, Kelso concluded, makes tools, machines, structures and processes ever more productive while leaving human productivity largely unchanged. The result is that primary distribution through the free market economy (whose distributive principle is "to each according to his production") delivers progressively more market-sourced income to capital owners and progressively less to workers who make their contributions through labor.