The traits the word 'childish' addresses are seen so often in adults that we should abolish this age-discriminatory word when it comes to criticizing behavior associated with irresponsibility and irrational thinking.
We all have some experience of a feeling, that comes over us occasionally, of what we are saying and doing having been said and done before, in a remote time - of our having been surrounded, dim ages ago, by the same faces, objects, and circumstances.
Man is guided by the stomach. He walks and the stomach goes first and the head afterwards. Have you not seen that? It will take ages for the head to go first.
In Bach there is still too much crude Christianity, crude Germanism, crude scholasticism; he stands on the threshold of European (modern) music, but he looks back from there to the Middle Ages.
He that seeketh to be eminent amongst able men hath a great task; but that is ever good for the public. But he that plots to be the only figure amongst ciphers is the decay of a whole age.