头脑可以断言任何事情，并假装已经证明了它。

The idea that we will make a society where literally everybody is graded, the good at the top, bad at the bottom, exactly done as it should be, is impossible. There are simply too many random factors: accidents, accidents of birth, accidents of things dropping on people's heads, illnesses, etc. We will never get to grade them, never get to grade people as they should.