How can great minds be produced in a country where the test of a great mind is agreeing in the opinions of small minds?

Mill's actual words:

"Is it astonishing that great minds are not produced, in a country where the test of a great mind is, agreeing in the opinions of the small minds?"

     John Stuart Mill, "Civilization" (1836), in The collected works of John Stuart Mill, vol. 18, Essays on politics and society, part 1 (Toronto:  University of Toronto Press; London: Routledge and Kegan Paul,  1977), .  Editor's note:  "Dissertations and Discussions, I (2nd ed., 1867), 160-205, where the title is footnoted, 'London and Westminster Review, April 1836.' Reprinted from L&WR, III & XXV (April, 1836), 1-28 [(p. 12, col. 2 in the American edition)], where it is headed, 'Art. I. / Civilization,' and has right running title 'Civilization' and left running title 'Signs of the Times.' Signed 'A.' Original article identified in JSM’s bibliography as 'An article entitled "Civilization—Signs of the Times" in the London and Westminster Review for April, (No 5 and 48.)' (MacMinn, 47.)"
     I should add that, after finding this in vol. 18, I did not search vols. 19-33 (though very roughly similar ideas occur in vols. 6 and 10 when searched on great minds).
     The quotation occurs as in the headline in, for example, The ordeal of Mark Twain, by Van Wyck Brooks (1920), 148.