Even as wisdom often comes from the mouths of babes, so does it often come from the mouths of old people. The golden rule is to test everything in the light of reason and experience, no matter from where it comes.
A man should learn to detect and watch that gleam of light which flashes across his mind from within, more than the luster of the firmament of bards and sages
... the random talk of people who have no chance of immortality and thus can speak their minds out has a setting, often, of lights, streets, houses, human beings, beautiful or grotesque, which will weave itself into the moment for ever.