Why is propaganda so much more successful when it stirs up hatred than when it tries to stir up friendly feeling? The reason is clearly that the human heart as modern civilisation has made it is more prone to hatred than to friendship. And it is prone to hatred because it is dissatisfied, because it feels deeply, perhaps even unconsciously, that it has somehow missed the meaning of life, that perhaps others, but not we ourselves, have secured the good things which nature offers man's enjoyment.
Source: The Conquest of Happiness, 1930, chap.6: Envy<
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