Income inequality is a topic Lean thinkers cannot avoid, even if many wish to do so. Income, whether from our time and expertise or from capital investments, is directly related to work.

The issue has become a political hot button because negative income growth over the last decade has been experienced by a large number of U.S. citizens. When the majority of people feel they are becoming wealthier large gaps in wealth and income matter less. When the majority of people feel they are becoming poorer, well then, Washington, we have a problem.

Plenty of people have staked their positions. A recent Chief Executive magazine article (January/February 2016) reports a range of views from ‘inequality being a necessary byproduct of capitalism and just fine’ to concerns that over concentrations of wealth will undermine prosperity.

Economist Thomas Piketty has fueled the argument with his 2014 book Capital in the Twenty-First Century. Aligned with the idea that over concentration of wealth is bad for society, it’s a well researched book with an excellent collection of data all intended to support the case for a global tax on wealth.

The book fails to explain why if concentrated wealth in the hands of relatively few individuals and families is bad, concentrating wealth even further into the hands of an even smaller number of governmental leaders is somehow better. Let’s not pretend that this global tax will be distributed equally to the citizens of the world. Piketty’s solution is Bulk thinking, perhaps at its absolute worst, with concentrations of capital in government hands constricting prosperity.

Capital in the Twenty-First Century does provide an approach to more even wealth and income distribution, even if Piketty has discounted the approach as unworkable. He presents an equation (economists love to reduce human behavior to mathematical equations) stating “r > g” with “r” representing the rate of return on capital and “g” the rate of economic growth. When the return on capital is higher than economic growth, which Piketty cites as the norm, income and wealth inequality grows. Periods when inequality shrank, such as during depressions, wars and post-war rebuilding periods, are aberrations to the norm as those periods fostered either negative capital returns or higher than normal “catch-up” economic growth.

Piketty projects return on capital rates through the end of the century to average four percent and economic growth in the same period to average one and one-half percent. His global tax on wealth is designed to lower the global return on capital such that the gap between capital return rates and economic growth shrinks to a level that shrinks the wealth inequality gap.

The flaw in Piketty’s thinking is that he believes the growth variable “g” in his equation is fixed and real growth at one and one-half percent per year isn’t going to increase appreciably. This limit on growth isn’t a given. A factor driving growth is productivity, which during the past ten years increased at a 1.3% annual rate and at a 2.9% annual rate the ten years prior. During the last forty years productivity growth has averaged about two percent.

In their book Real Numbers: Management Accounting in a Lean Organization Jean Cunningham and Orest Fiume assert that a Lean enterprise should expect productivity increases between eight and fifteen percent, far above the historical two percent increase. Back of the envelope math suggests that if just half the economy began working on a Lean basis “g” would increase such that Piketty’s equation “r > g” would reverse to “r < g” and as a result income inequality would shrink. More importantly, the growth in prosperity would be shared among significantly more people.

Is it realistic that at least half of the economy begins to work on a Lean basis? More so than Piketty’s global tax on wealth, and without the unintended negative consequences such a tax would bring. A global tax on wealth requires an immense level of coordination. The transition to a Lean economy requires that enterprises, one-by-one, pick up the Lean banner and begin their journey.