
The theories of progressive income taxation developed in the Italian debate of the last century have been discussed in depth in a review article by Domenican-tonio Fausto (2008). Italian economists have taken an active part in the debate on the progressive taxation of income and wealth. In general, despite a few oppo-nents, the idea of progressive taxation is agreed upon for political and social rea-sons. In this broad debate on progressivity developed in Italy, there is also an ana-lytical path that Fausto’s article does not consider. The first mathematical contri-bution on this topic was put forward by Tullio Martello in his polemic book against the progressive tax, La progressività in teoria e in pratica (1895). The debate was concluded in the 1950s by a mathematical economist and follower of Pareto, Raf-faele D’Addario. D’Addario is worth considering because he explicitly introduced the revenue curve. The decreasing part is well known today as the Laffer curve.