What a man knows at fifty that he did not know at twenty is, for the most part, incommunicable. The laws, the aphorisms, the generalizations, the universal truths, the parables and the old saws — all of the observations about life which can be communicated handily in ready, verbal packages — are as well known to a man at twenty who has been attentive as to a man at fifty. He has been told them all, he has read them all, and he has probably repeated them all before he graduates from college; but he has not lived them all.

Adlai Stevenson (1900-1965) American diplomat, statesman

“The Educated Citizen,” Address, Princeton University (22 Mar 1954)

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