We amuse ourselves painting our prison-walls with bright figures and brilliant landscapes.

No doubt you are right... there would be far less suffering amongst mankind if men... did not employ their imaginations so assiduously in recalling the memory of past sorrow, instead of bearing their present lot with equanimity.

A resolution that is communicated is no longer within thy power; thy attentions become now the plaything of chance; he who would have his commands certainly carried out must take man by surprise.

Should I not be proud, when for twenty years I have had to admit to myself that the great Newton and all the mathematicians and noble calculators along with him were involved in a decisive error with respect to the doctrine of color, and that I among millions was the only one who knew what was right in this great subject of nature?

A flippant, frivolous man may ridicule others, may controvert them, scorn them; but he who has any respect for himself seems to have renounced the right of thinking meanly of others.

Dispel not, the happy delusions of children.

It is unpleasant to miss even the most trifling thing to which we have been accustomed.