My contemplation of life and human nature in that secluded place [cell 54 of Cairo Central Prison] taught me that he who cannot change the very fabric of his thought will never, therefore, make any progress.

Adaptability is imitation. It means power of resistance and assimilation.

The art of life lies in a constant readjustment to our surroundings.

Man's unique reward ... is that while animals survive by adjusting themselves to their background, man survives by adjusting his background to himself.

We are descended from India rubber... . That's why our forefathers and the slaves who were sent to America were able to adapt themselves to a situation that was new to them.

Each person lives his life in this world according to his own times; Whether to come forth and serve, or to retire in withdrawal, is not a fortuitous decision.