In the absence of disturbing factors, therefore, it should be possible to trace a difference of temperament between the classes of society.

The aristocratic and the bourgeois virtues--that is to say the destructive and pecuniary traits--should be found chiefly among the upper classes, and the industrial virtues--that is to say the peaceable traits--chiefly among the classes given to mechanical industry.
In a general and uncertain way this holds true, but the test is not so readily applied nor so conclusive as might be wished.

There are several assignable reasons for its partial failure.

All classes are in a measure engaged in the pecuniary struggle, and in all classes the possession of the pecuniary traits counts towards the success and survival of the individual.

Wherever the pecuniary culture prevails, the selective process by which men's habits of thought are shaped, and by which the survival of rival lines of descent is decided, proceeds proximately on the basis of fitness for acquisition.