Karl Groos

Karl Groos (1861 to 1946) was a German philosopher and psychologist who proposed an evolutionary instrumentalist theory of play. Born in Heidelberg, he was full professor of philosophy at Giessen, then Basel, and from 1911 to 1929 at Tübingen, where he died. His 1898 book The Play of Animals, the English translation of his German work of 1896 by J. Mark Baldwin, argued that play is a preparation for later life: because play is useful, it can be explained by natural selection, and animals at play are practising basic instincts such as fighting that they will need for survival. He followed it with The Play of Man in 1899, and also wrote on aesthetics, the inner life of the child and the psychology of literature, including statistical analysis. His work is seldom read today, and his connection of play with aesthetics has been called misguided, but the sentence about growing old because we stop playing, often credited to others, is attributed to him in the 2018 film Tag.