At thirty a professional man is younger than the business man of twenty-five. Less is expected of him; his work is less responsible; he has not been so long on his job. At forty the doctor or lawyer may still achieve an unexpected success. He has hardly won his spurs, though in his heart he well knows his own limitations. He can still say: "I am young yet!" And he is.But at fifty! Ah, then he must face the facts! He either has or has not lived up to his expectations and he never can begin over again. A creature of physical and mental habit, he must for the rest of his life trudge along in the same path, eating the same food, thinking the same thoughts, seeking the same pleasures - until he acknowledges with grim reluctance that he is an old man.I confess that I had so far deliberately tried to forget my approaching fiftieth milestone, or at least to dodge it with closed eyes as I passed it by, that my daughter's polite congratulation on my demicentennial anniversary gave me an unexpected and most unpleasant shock."You really ought to be ashamed of yourself!" she remarked as she joined me at breakfast."Why?" I asked, somewhat resenting being thus definitely proclaimed as having crossed into the valley of the shadows."To be so old and yet to look so young!" she answered, with charming voir-faire.