George Santayana and Henry Spencer can tell you. Santayana in 1905: "Those who cannot remember the past are condemned to repeat it." Spencer in 1987: "Those

George Santayana and Henry Spencer can tell you. Santayana in 1905: "Those who cannot remember the past are condemned to repeat it." Spencer in 1987: "Those who do not understand Unix are condemned to reinvent it, poorly."