In the first part I surveyed the social issues of the middle and last years of the nineteenth century, and the nature of popular secularization. We saw how social investigation proved a large amount of social motive rather than intellectual; that when, for example, members of the German Social Democratic party favoured what was known as materialism, they cared not for the academic arguments for materialistic philosophies of life. We saw how investigation veered away from the kind of history not too uncommon until 1900, where secularization was identified with advancing knowledge, and started to concentrate on the nature of popular movements and the way in which ideas make their impact upon or among them, the pre-conditions in society which make old ideas obsolete and new ideas magnetic.

Whereas the Whig Protestant historian saw the falling away in churches as a sign of more information, and thought that the young need only to go to better schools to jettison ancient necromancies of illiterate parents, sociologists turned their attention to elements which constitute human society, and instantly ran into the force of religion, as an instrument of social consensus, family or community habit, public and civic rites, and even social control. Then Marxist historians, who proved that our heads are not so distant from our bellies as Whigs seemed to think, diverted attention further from the history of ideas as ideas, to force us to alter our perspective of the way in which social ideas change.