Aquellos que no pueden recordar el pasado están condenados a repetirlo. (Those who cannot remember the past are condemned to repeat it.)
George Santayana in La Vida de la Razón, Volumen 1: La razón en el Sentido Comú, 1905
The statement has been re- and paraphrased numerous times, e.g.
- Those who cannot learn from history are doomed to repeat it.
- Those who do not remember their past are condemned to repeat their mistakes.
- Those who do not read history are doomed to repeat it.
- Those who fail to learn from the mistakes of their predecessors are destined to repeat them.
- Those who do not know history’s mistakes are doomed to repeat them.