Progress is impossible without change, and those who cannot change their minds cannot change anything.

• An index is a great leveller.
• He's a man of great common sense and good taste - meaning thereby a man without originality or moral courage.
• Just do what must be done. This may not be happiness, but it is greatness.
• It is a curious sensation: the sort of pain that goes mercifully beyond our powers of feeling. When your heart is broken, your boats are burned: nothing matters any more. It is the end of happiness and the beginning of peace.
• We have no more right to consume happiness without producing it than to consume wealth without producing it.
• Give a man health and a course to steer, and he'll never stop to trouble about whether he's happy or not.
• Use your health, even to the point of wearing it out. That is what it is for. Spend all you have before you die do not outlive yourself.
• If history repeats itself, and the unexpected always happens, how incapable must Man be of learning from experience.
• Hegel was right when he said that we learn from history that man can never learn anything from history.
• Home life is no more natural to us than a cage is natural to a cockatoo.