"Few books have exercised so pernicious an influence upon the general development of economic thought as Malthus's Essay on the Principle of Population exercised for three consecutive generations. It appeared at the right time, like all books which have had any influence... and it summed up the ideas already current in the minds of the wealth-possessing minority. It was precisely when the ideas of equality and liberty, awakened by the French and American revolutions, were still permeating in the minds of the poor, while the richer classes had become tired of their amateur excursions into the same domains, that Malthus came to assert, in reply to Godwin, that no equality is possible; that the poverty of the many is not due to institutions, but is a natural law... and that law cannot be changed by any change of institutions."