For the unlearned, old age is winter; for the learned it is the season of the harvest.  The Talmud quotes Study until 25, investigate until 40, profession until 60, at which age I would have him retired on a double allowance. William Osler quotes Wisdom is the gray hair unto men, and an unspotted life is old age (Solomon 4:8). The Bible quotes He who does not have common sense at age thirty will never have it. Proverb quotes Let us never know what old age is. Let us know the happiness time brings, not count the years. Ausonius quotes The old age of an eagle is better than the youth of a sparrow. Proverb quotes Probably the happiest period in life most frequently is in middle age, when the eager passions of youth are cooled, and the infirmities of age not yet begun; as we see that the shadows, which are at morning and evening so large, almost entirely disappear at midday. Thomas Arnold quotes The great difficulty is first to win a reputation; the next to keep it while you live; and the next to preserve it after you die, when affection and interest are over, and nothing but sterling excellence can preserve your name. Never suffer youth to be an excuse for inadequacy, nor age and fame to be an excuse for indolence. Benjamin Haydon quotes Middle age is when your age starts to show around your middle. Bob Hope quotes Within us all there are wells of thought and dynamos of energy which are not suspected until emergencies arise. Then often times we find that it is comparatively simple to double or triple our former capacities and to amaze ourselves by the results achieved. Quotas, when set up for us by others, are challenges which goad us on to surpass ourselves. The outstanding leaders of every age are those who set up their own quotas and constantly achieve them. Thomas J. Watson, Sr. quotes | 
