Professor Yoshino explains. "Shakespeare calls this a problem of ocular proof, the idea that we need to see evidence before we believe in it -- and that,oftentimes, when metaphysical questions of guilt or innocence are difficult for us to answer, we have a tendency to reduce them to questions that pertain to physical evidence.

VOA: special.2011.06.06

So again, this is how we kind of feel the article proof.

我们又一次,证明了大脑的关键性。

耶鲁公开课 - 死亡课程节选

He says Poland is now ready to be a responsible co-leader in Europe, and this signature is proof of that.

VOA: standard.2009.10.10