In science the important thing is to modify and change one's ideas as science advances.

Those who have never entered upon scientific pursuits know not a tithe of the poetry by which they are surrounded.

In societies of low civilization, there is no money.

Marriage: A word which should be pronounced "mirage".

No one can be perfectly free till all are free; no one can be perfectly moral till all are moral; no one can be perfectly happy till all are happy.

Those whose hardships are set forth in pamphlets and proclaimed in sermons and speeches which echo throughout society, are assumed to be all worthy souls, grievously wronged; and none of them are thought of as bearing the penalties of their misdeeds.

So long as selfishness makes government needful at all, it must make every government corrupt, save one in which all men are represented.