To go out of your mind once a day is tremendously important, because by going out of your mind you come to your senses. And if you stay in your mind all of the time, you are over rational, in other words you are like a very rigid bridge which because it has no give; no craziness in it, is going to be blown down by the first hurricane.

There are books which we read early in life, which sink into our consciousness and seem to disappear without leaving a trace. And then one day we find, in some summing-up of our life and put attitudes towards experience, that their influence has been enormous.

Hope is a very unruly emotion.

It does not matter how frequently something succeeds if failure is too costly to bear.

I am not sure that it is of the first importance that you should be happy. Many an unhappy man has been of deep service to himself and to the world.

I’ve never been certain whether the moral of the Icarus story should only be, as is generally accepted, ‘don’t try to fly too high,’ or whether it might also be thought of as ‘forget the wax and feathers, and do a better job on the wings.