The Laffer curve is a compelling economic concept. It claims that government revenue as a function of tax rates is shaped as an inverted-U. This means that, at first, raising the tax rate from zero will increase tax rates. However, there is some tax rate which maximizes government revenue (but not necessarily social welfare). When tax rates are increased beyond this point, however, tax revenues decrease because as income taxes rise, the disincentive to work becomes sufficiently great that the higher per hour amount of tax receipts will be more than offset by the workers incentive to work less hours.
The theory is theoretically sound and elegant, but do economists actually know what the tax rate which maximizes government revenue will be?
The mathematician Martin Gardner claims not. His satirical construct called the neo-Laffer curve (see image). According to Wikipedia, “The neo-Laffer curve matches the original curve near the two extremes of 0% and 100%, but rapidly collapses into an incomprehensible snarl of chaos at the middle. Gardner based his curve on actual US economic data collected in a fifty year period by statistician Persi Diaconis.”
Gardner makes the sound point that the Laffer curves is very appropriate for theoretical analysis and as a pedagogical tool, but it does not sufficiently reflect reality in order for politicians to make tax policy based on the construct.