[伊索寓言] 骡子

The Mule 

A mule had grown fat and wanton(无节制的) from his huge daily rations(口粮) of corn, and one day, as he was jumping, kicking, and gamboling(飞驰) about the fields...”My mother must surely have been a thoroughbred(纯种的) racer...

...and all at once he remembered that his sire(祖先) had been nothing but a donkey.

Every truth has two sides.  It is best to look at both before we declare where we stand.