It is quite customary to associate the term "sage" with some ancient gentleman whose long grey beard is supposed to make him as wise as his years. But an old man is not necessarily much wiser than a young one. Wisdom cannot be measured by the calendar. We should not respect the years but their fruit. If a man has found wisdom at the cost of his years, we should respect him. But we should not fall into the concealed if persuasive fallacy of respecting his beard. The term "sage" also gives rise in many minds to the picture of a creature belonging to an extinct species, a boring creature with pompous speech and portentous manner. Yet the lack of ability to laugh at themselves--and certainly the lack of any sense of humour at all--characterizes fools and not sages.
-- Notebooks Category 25: World-Mind in Individual Mind > Chapter 3: The Sage > # 380