“A happy wall is a long-lived wall, a practical wall, a useful wall.”

“A wall is happy when it is well designed, when it rests firmly on its foundation, when its symmetry balances its part and produces no unpleasant stresses. Good design can be worked out on the mathematical principles of mechanics.”

“all the suffering that humanity ever knew can be traced to the one fact that no man in the history of the Galaxy, until Hari Seldon, and very few men thereafter, could really understand one another. Every human being lived behind an impenetrable wall of choking mist within which no other but he existed. Occasionally there were the dim signals from deep within the cavern in which another man was located - so that each might grope toward the other. Yet because they did not know one another, and could not understand one another, and dared not trust one another, and felt from infancy the terrors and insecurity of that ultimate isolation - there was the hunted fear of man for man, the savage rapacity of man toward man.”

“Naturally, there's got to be a limit for I don't expect to live forever, but I do intend to hang on as long as possible.”

“I wanted to be a psychological engineer, but we lacked the facilities, so I did the next best thing - I went into politics. It's practically the same thing.”

“But life is glorious when it is happy; days are carefree when they are happy; the interplay of thought and imagination is far superior to that of muscle and sinew. Let me tell you, if you don't know it from your own experience, that reading a good book, losing yourself in the interest of words and thoughts, is for some people (me, for instance) an incredible intensity of happiness.”

“There are no happy endings in history, only crisis points that pass.”