保持冷静，但要关心。

在没有生命力的帮助下合成尿素是一个极其重要的事实。

The books that everybody admires are those that nobody reads.

No testimony is sufficient to establish a miracle unless the testimony be of such a kind that its falsehood would be more miraculous than the fact which it endeavors to establish.

Nature does not waste, and neither should we.