The scientists conclude that our aversion to bad behavior and to bad food may have evolved from a primitive defense mechanism that nowadays protects us from both insult and injury.

科学家们得出的结论是：我们对不良行为和糟糕食物的讨厌可能从一种原始的防御机制进化而来，进化到今天，这种防御机制既能保护我们免于受到侮辱，也能防止我们受到伤害。

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Splitting is a primitive psychological defense mechanism used to make difficult people in our lives seem all good, or all bad, as needed.

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