A happy life must be to a great extent a quiet life, for it is only in an atmosphere of quiet that true joy dare live.

I believe that the abolition of private ownership of land and capital is a necessary step toward any world in which the nations are to live at peace with one another.

Happiness, as is evident, depends partly upon external circumstances and partly upon oneself.

The solution of the difficulties which formerly surrounded the mathematical infinite is probably the greatest achievement of which our age has to boast.

I believe that when I die I shall rot, and nothing of my ego will survive. I am not young, and I love life. But I should scorn to shiver with terror at the thought of annihilation. Happiness is nonetheless true happiness because it must come to an end, nor do thought and love lose their value because they are not everlasting.

We may define "faith" as the firm belief in something for which there is no evidence. Where there is evidence, no one speaks of "faith." We do not speak of faith that two and two are four or that the earth is round. We only speak of faith when we wish to substitute emotion for evidence. The substitution of emotion for evidence is apt to lead to strife, since different groups, substitute different emotions.

The essence of the liberal outlook lies not in what opinions are held, but in how they are held; instead of being held dogmatically, they are held tentatively, and with a consciousness that new evidence may at any moment lead to their abandonment.