"Be kind..."

 

"Benevolence [alone] is inadequate for the task of building cooperation in a large society, because we are irredeemably biased in our benevolence to relatives and close friends; a society built on benevolence would be riddled with nepotism. Between strangers, the invisible hand of the market, distributing selfish ambitions, is fair."

~ Adam Smith, from his Theory of Moral Sentiments (as summarised by Matt Ridley)

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