It is better to be Socrates dissatisfied than a pig satisfied.

Next to selfishness the principal cause which makes life unsatisfactory is want of mental cultivation.

Everything must be free to be written and published without restraint.

The human faculties of perception, judgment, discriminative feeling, mental activity, and even moral preference, are exercised only in making a choice. He who does anything because it is the custom, makes no choice.

Men and governments must act to the best of their ability. There is no such thing as absolute certainty but there is assurance sufficient for the purposes of human life.

I know tolerably well what Ireland was, but have a very imperfect idea of what Ireland is.

Men might as well be imprisoned, as excluded from the means of earning their bread.