All our knowledge begins with the senses proceeds then to the understanding and ends with reason. There is nothing higher than reason.

Even the knowledge of my own fallibility cannot keep me from making mistakes. Only when I fall do I get up again.

Knowledge has to be improved challenged and increased constantly or it vanishes.

One whose knowledge is confined to books and whose wealth is in the possession of others can use neither his knowledge nor wealth when the need for them arises.

We know accurately only when we know little with knowledge doubt increases.

Let us tenderly and kindly cherish therefore the means of knowledge. Let us dare to read think speak and write.

Doubt grows with knowledge.

Knowledge is true opinion.

Knowledge which is acquired under compulsion obtains no hold on the mind.

The possession of knowledge does not kill the sense of wonder and mystery. There is always more mystery.