It is in the twenties that ...

It is in the twenties that the actual momentum of life begins to slacken, and it is a simple soul indeed to whom as many things are as significant and meaningful at thirty as at ten years before. At thirty an organ-grinder is a more or less a moth eaten man who grinds an organ - and once he was an organ-grinder! The unmistakable stigma of humanity touches all those impersonal and beautiful things that only youth ever grasps in their impersonal glory.
It is in the twenties that the actual momentum of life begins to slacken, and it is a simple soul indeed to whom as many things are as significant and meaningful at thirty as at ten years before. At thirty an organ-grinder is a more or less a moth eaten man who grinds an organ - and once he was an organ-grinder! The unmistakable stigma of humanity touches all those impersonal and beautiful things that only youth ever grasps in their impersonal glory.

Quotes from the same author

When a man is tired of life on his 21st birthday it indicates that he is rather tired of something in himself.
Thirty--the promise of a decade of loneliness, a thinning list of single men to know, a thinning brief-case of enthusiasm, thinning hair.
mother says that two souls are sometimes created together and--and in love before they're born.
Never confuse activity with action.
I think they're very attractive,' Abe agreed. 'I just don't think they're attractive, that's all.