"The rule of thumb based into the brain by natural selection would not have been, Be nice to your kin and be nice to potential reciprocators. It would have been, Be nice to everybody, because everybody would have been included."

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Divers alarums and excursions', she read, uncertainly. 'That means lots of terrible happenings, said Magrat. 'You always put that in plays.' Alarums and what?', said Nanny Ogg, who hadn't been listening. Excursions', said Magrat patienly. Oh.' Nanny Ogg brightened a bit. 'The seaside would be nice,' she said. Oh do shut up, Gytha,' said Granny Weatherwax. 'They're not for you. They're only for divers, like it says. Probably so they can recover from all them alarums.

— Terry Pratchett