I did get my Doctor's degree and stayed in Leipzig. Heisenberg employed me as an assistant to his assistant, Bloch, and Bloch and I sat together evenings and corrected students' papers. You know, I learned a lot by correcting papers. Because what Bloch and I learned - and I'm very grateful for it - I learned in answering a question: what are all the mistakes that one can make? And I believe to this day that a complete understanding of a subject, or at least an approach to complete understanding, is precisely to understand all the wrong answers that you can give. In the course of time, I got an invitation from Göttingen, from a physical chemist by the name of Eucken. And maybe a little less than a year after my PhD degree, in 1931, I decided to go to Göttingen. My main learning years, not all of them, but the great shock of novelty of quantum mechanics, was over. It was now my job to transfer this knowledge which at that time, in 1931, was not very widely spread. The physical chem- physical chemists hardly knew it. I went around with Eucken when he visited his research students and I helped in the discussions. As an assistant, I really believe at that time I did more teaching than at any time in my life. There was a second man in Göttingen with whom I soon get acquainted- got acquainted and my job as assistant of Eucken got transformed into a job of assistant of Eucken and James Franck, an exceptionally nice man who got the Nobel Prize for something I will tell you in a moment. He took me on, on his newly acquired car, in which he was- took a lot of pride, to show me Göttingen, and told me about Bohr. He said- You know, Bohr's statement, he was now talking about the early '20s, or maybe the late 10- Bohr's statement of excited states of atoms was completely crazy. None of us believed it. But Bohr was such a nice man, we thought we should try it anyway. And that is why I got the Nobel Prize. What he was talking about was the famous experiment of himself and Hertz, to have isolated atoms and shoot on that electrons- on that atom, electrons. And the electrons would be scattered, come off in another direction, with the s- practically with the same energy, no loss of energy. Then we got to higher and higher energies. And at a certain energy, the electron dec- decided, now we can lose energy. You surpass that critical energy by 5%, some of the electrons lost all but 5% of their energy. We had very clear experimental proof that atoms will not accept any energy but starting from a minimum energy, which is the energy of the first excited state, in Bohr, that they could take up. That's why we got the Nobel Prize. And actually, this is, as I understand it, an important representation of the early part of atomic energy. That transformed Niels Bohr from a very nice man with some absurd ideas into a real genius. Because here the absurd ideas, were proven in an entirely different way.