"In this galaxy of stars von Neumann, a professor at the Institute, simply radiated excitement. His lectures on Hilbert Space, measure theory, rings of operators (called now von Neumann algebras), and continuous geometry, fascinated a large audience. At the daily afternoon tea he engaged some group in a most lively and stimulating discussion. With obvious delight he explained, clarified, and analyzed problems on the spot and gave help to one and all. But sometimes he would stand apart, deep in thought, his brown eyes staring into space, his lips moving silently and rapidly, and at such times no one ventured to disturb him."