'Men are docile to events, plastic to new habits and suggestions... This is the plane of manhood and true progress.' -George Santayana
From Spanish-American philosopher George Santayana's The Life of Reason, this quote distinguishes the second, mature stage of life from the first ("the condition of children and barbarians") and the third ("old age is as forgetful as youth, and more incorrigible"). On the subject of progress relying on the foundation that immediately precedes it, this passage is responsible for the well-known phrase "Those who cannot remember the past are condemned to repeat it," often misattributed to countless other writers of various eras.
