你知道什么是“金发姑娘原则”吗？

　　大家有没有看过童话《金发姑娘和三只熊》呢？迷路了的金发姑娘未经允许就进入了熊的房子，她尝了三只碗里的粥，试了三把椅子，又在三张床上躺了躺，最后决定小碗里的粥最可口，小椅子坐着最舒服，小床上躺着最惬意，因为那是最适合她的，不大不小刚刚好。金发姑娘选择事物的原则就叫Goldilocks principle（金发姑娘原则）。

　　The Goldilocks principle states that something must fall within certain margins, as opposed to reaching extremes. When the effects of the principle are observed, it is known as the Goldilocks effect.

　　“金发姑娘原则”指出，凡事都必须有度，而不能超越极限。按照这一原则行事产生的效应就称为“金发姑娘效应”。

　　The Goldilocks principle is derived from a children's story "The Three Bears" in which a little girl named Goldilocks finds a house owned by three bears. Each bear has their own preference of food and beds. After testing all three examples of both items, Goldilocks determines that one of them is always too much in one extreme (too hot or too large), one is too much in the opposite extreme (too cold or too small), and one is "just right".

　　“金发姑娘原则”源自童话《金发姑娘和三只熊》的故事。金发姑娘发现了三只熊的房子，每只熊都有自己喜欢的食物和床。在挨个尝试过三只熊的食物和床后，金发姑娘发现有一个要么太大/太热，一个要么太小/太凉，只有一个是“刚刚好”。

　　In astrobiology, the Goldilocks zone refers to the habitable zone around a star. In economics, a Goldilocks economy sustains moderate economic growth and low inflation.

　　在天文学里，“金发姑娘地带”指的是一个星球周围的宜居地带。在经济学里，“金发姑娘经济”指的是维持适度增长和低通胀的经济。