The income tax is a much less effective tool for reducing inequalities than has often been thought. - James Mirrlees

An approximately linear income tax schedule is desirable; and in particular negative income tax proposals are strongly supported,

Economics takes a while to learn, even if much of it is in a way quite simple. It is simple to be wrong as well as to be right, and it is none too easy to distinguish between them.

I must confess that I had expected the rigorous analysis of income taxation in the utilitarian manner to provide arguments for high tax rates. It has not done so.