The hours of folly are measured by the clock, but of wisdom: no clock can measure.

In our reasonings concerning matter of fact， there are all imaginable degrees of assurance， from the highest certainty to the lowest species of moral evidence.

农业效率不仅仅关乎产量；它还涉及资源的负责任使用。

生命最大的用途是将其投入到比生命更持久的事物中。

酸的强度由其提供质子的能力来衡量，碱的强度由其接受质子的能力来衡量。

爱不是容易的事。