Consider the Negro as a neighbor. He is frequently repelled and avoided by the white man, but is it only color prejudice? On the contrary, it is beca… - George Stigler

Price dispersion is a manifestation — and, indeed, it is the measure — of ignorance in the market. Dispersion is a biased measure of ignorance because there is never absolute homogeneity in the commodity if we include the terms of sale within the concept of the commodity. Thus, some automobile dealers might perform more service, or carry a larger range of varieties in stock, and a portion of the observed dispersion is presumably attributable to such differences. But it would be metaphysical, and fruitless, to assert that all dispersion is due to heterogeneity.

In the 1950s, I proposed the survivor method of determining the efficient sizes of enterprises, and worked on delivered price systems, vertical integration, and similar topics.

The user of a theory has a simpler task: his not to reason why, his but to sigh and try. If the right element in the diverse situations has been isolated, the theory will work: it will yield predictions better than those which can be reached with any alternative theory.