Our observation of nature must be diligent, our reflection profound, and our experiments exact. We rarely see these three means combined; and for this reason, creative geniuses are not common.
There are three principal means of acquiring knowledge. . . observation of nature, reflection, and experimentation. Observation collects facts; reflection combines them; experimentation verifies the result of that combination.
You can use all the quantitative data you can get, but you still have to distrust it and use your own intelligence and judgment.
The illiterate of the future will not be the person who cannot read. It will be the person who does not know how to learn.
Honest differences are often a healthy sign of progress.