Delboeuf observed that if two circles the same size were placed inside two other circles that were different sizes, the same-sized inner circles would also seem to be different sizes.

Delboeuf观察到如果将两个同样大小的圆分别放在另外两个不同大小的圆里面，两个同样的圆看起来大小会不一样。

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Delboeuf observed that if two circles the same size were placed inside two other circles that were different sizes, the same-sized inner circles would also seem to be different sizes.

Delboeuf观察到如果将两个同样大小的圆分别放在另外两个不同大小的圆里面，两个同样的圆看起来大小会不一样。

youdao