The particular point of view, or the particular characteristic that is pitched upon as definitive in the classification of the facts of life depends upon the interest from which a discrimination of the facts is sought.

The grounds of discrimination, and the norm of procedure in classifying the facts, therefore, progressively change as the growth of culture proceeds; for the end for which the facts of life are apprehended changes, and the point of view consequently changes also.

So that what are recognised as the salient and decisive features of a class of activities or of a social class at one stage of culture will not retain the same relative importance for the purposes of classification at any subsequent stage.
But the change of standards and points of view is gradual only, and it seldom results in the subversion or entire suppression of a standpoint once accepted.

A distinction is still habitually made between industrial and non-industrial occupations; and this modern distinction is a transmuted form of the barbarian distinction between exploit and drudgery.

Such employments as warfare, politics, public worship, and public merrymaking, are felt, in the popular apprehension, to differ intrinsically from the labour that has to do with elaborating the material means of life.