It would be trite to remark about my awareness of the distinction conferred upon a speaker in extending to him the invitation to deliver this memorial address. Nonetheless, there is distinction in being associated, as Richtmyer lecturer, with such men as Compton, Hull, Darrow and Rabi; and there is distinction in being selected by his fellows as one whom they regard capable of making a contribution of interest to the two distinguished societies here assembled. Finally, there is distinction in the assignment of honoring the memory of a man who contributed so much to physics, and whom the speaker was privileged to count among his friends. In preparing this address, I have been sensitive to the obligation of demonstrating that the Committee exercised good judgment.
