Does the richness of the few benefit us all?

It is commonly assumed that the best way to help the poor out of their misery is to allow the rich to get richer, that if the rich pay less taxes then all the rest of us will be better off, and that in the final analysis the richness of the few benefits us all. And yet these commonly held beliefs are flatly contradicted by our daily experience, an abundance of research findings and, indeed, logic. Such bizarre discrepancy between hard facts and popular opinions makes one pause and ask: why are these opinions so widespread and resistant to accumulated and fast-growing evidence to the contrary?