Given this possibility of simple exit from any and all of the European tax systems (and such exit does not require that one stays in the EU either) the theoretical peak of the Laffer Curve is lower in Europe than it is in the US. Where such exit is very much more difficult.

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In his book, Mr Sen raised the theoretical possibility that a pastoralist's supply curve might actually bend back on itself: as the relative price of livestock falls, a hungry pastoralist might supply more animals to the market, not fewer as elementary economic principles would imply.

ECONOMIST: Economics focus

There is one theoretical way out of this dilemma: Supply-side economics, featuring the Laffer Curve, which under some circumstances enables us to have our cake and eat it too.

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