If anyone is crazy enough to want to kill a president of the United States, he can do it. All he must be prepared to do is give his life for the president's.

He who is not everyday conquering some fear has not learned the secret of life.

The greatest gift of life is friendship, and I have received it.

Life is without meaning. You bring the meaning to it. The meaning of life is whatever you ascribe it to be. Being alive is the meaning.

The world is very different now. For man holds in his mortal hands the power to abolish all forms of human poverty, and all forms of human life.