I've worked for three ESOPs and was curious about their history. Learning about Binary Economics has led me into an interest in alternative economic theories. There are sites and books dedicated to the subject, the following excerpt from the previously linked wikipedia page was the connection I had made, but really he was trying to solve problems related to measuring production with regards to automation. With the advent of the computer age, it was viewed as inevitable.
`Binary productiveness is distinctly different from the conventional economic concept of productivity. Binary productiveness attempts to quantify the proportion of output contributed by total labor input and total capital input respectively, Adding capital inputs to a production process increases labor productivity, but binary economic theory argues that it decreases labor productiveness (i.e. the proportion of the total output with the support of both labor and capital that the labor inputs could have produced alone). For example, if the invention of a shovel allows a laborer to dig a hole in quarter of the time it would take him without the spade, binary economists would consider 75% of the "productiveness" to come from the shovel and only 25% from the laborer.`
`Kelso used the concept of productiveness to support his theory of distributive justice, arguing that as capital increasingly substitutes for labor..."workers can legitimately claim from their aggregate labor only a decreasing percentage of total output", implying they would need to acquire capital holdings to maintain their level of income.`
and
`...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.`