An amino acid residue (other than glycine) has no symmetry elements. The general operation of conversion of one residue of a single chain into a second residue equivalent to the first is accordingly a rotation about an axis accompanied by translation along the axis. Hence the only configurations for a chain compatible with our postulate of equivalence of the residues are helical configurations.

I have something that I call my Golden Rule. It goes something like this: 'Do unto others twenty-five percent better than you expect them to do unto you.' … The twenty-five percent is for error.

It has been recognized that hydrogen bonds restrain protein molecules to their native configurations, and I believe that as the methods of structural chemistry are further applied to physiological problems it will be found that the significance of the hydrogen bond for physiology is greater than that of any other single structural feature.

Life is a relationship among molecules and not a property of any molecule.

Men will gather knowledge no matter what the consequences. Science will go on whether we are pessimistic or optimistic, as I am. More interesting discoveries than we can imagine will be made, and I am awaiting them, full of curiosity and enthusiasm.

I recognize that many physicists are smarter than I am-most of them theoretical physicists. A lot of smart people have gone into theoretical physics, therefore the field is extremely competitive. I console myself with the thought that although they may be smarter and may be deeper thinkers than I am, I have broader interests than they have.

We must have research for peace ... It would embrace the outstanding problems of morality. The time has come for man's intellect, his scientific method, to win over the immoral brutality and irrationality of war and militarism ... Now we are forced to eliminate from the world forever this vestige of prehistoric barbarism, this curse to the human race.