Why fun is fun

To exercise one’s capacities to their fullest extent is to take pleasure in one’s own existence, and with sociable creatures, such pleasures are proportionally magnified when performed in company. From the Russian perspective, this does not need to be explained. It is simply what life is. We don’t have to explain why creatures desire to be alive. Life is an end in itself. And if what being alive actually consists of is having powers—to run, jump, fight, fly through the air—then surely the exercise of such powers as an end in itself does not have to be explained either. It’s just an extension of the same principle.
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Reconsider the lobster. Lobsters have a very bad reputation among philosophers, who frequently hold them out as examples of purely unthinking, unfeeling creatures. Presumably, this is because lobsters are the only animal most philosophers have killed with their own two hands before eating. It’s unpleasant to throw a struggling creature in a pot of boiling water; one needs to be able to tell oneself that the lobster isn’t really feeling it. (The only exception to this pattern appears to be, for some reason, France, where Gérard de Nerval used to walk a pet lobster on a leash and where Jean-Paul Sartre at one point became erotically obsessed with lobsters after taking too much mescaline.) But in fact, scientific observation has revealed that even lobsters engage in some forms of play—manipulating objects, for instance, possibly just for the pleasure of doing so. If that is the case, to call such creatures “robots” would be to shear the word “robot” of its meaning. Machines don’t just fool around. But if living creatures are not robots after all, many of these apparently thorny questions instantly dissolve away.
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The very fact that you felt compelled to try to beat me in an argument, and were so happy to be able to do so, shows that the premise you were arguing must be false. Since if even philosophers are motivated primarily by such pleasures, by the exercise of their highest powers simply for the sake of doing so, then surely this is a principle that exists on every level of nature—which is why I could spontaneously identify it, too, in fish.

David Graeber explains.