If a man or woman who is healthy and has enough to eat is to be happy, there is need of two things that, at first sight, might seem antagonistic. There is need, first, of a stable framework built round a central purpose, and second, of what may be called "play," that is to say, of things that are done merely because they are fun, and not because they serve some serious end.
Source: Bertrand Russell: The road to happiness (1952)
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