The credit of advancing science has always been due to individuals and never to the age.

One can be instructed in society, one is inspired only in solitude.

Energy is the basis of everything. Every Jew, no matter how insignificant, is engaged in some decisive and immediate pursuit of a goal... It is the most perpetual people of the earth.

Every step of life shows much caution is required.

All that is alive tends toward color, individuality, specificity, effectiveness and opacity. All that is done with life inclines toward knowledge, abstraction, generality transfiguration and transparency.

Judge a man's character by what he finds ridiculous.

It is in the half fools and the half wise that the greatest danger lies.