Modern complexities call also for a constant infusion of new blood in the courts, just as it is needed in executive functions of the Government and in private business. A lowered mental or physical vigor leads men to avoid an examination of complicated and changed conditions. Little by little, new facts become blurred through old glasses fitted, as it were, for the needs of another generation; older men, assuming that the scene is the same as it was in the past, cease to explore or to inquire into the present or the future.