I believe that we can still have a genre of scientific books suitable for and accessible alike to professionals and interested laypeople. The concepts of science, in all their richness and ambiguity, can be presented without any compromise, without any simplification counting as distortion, in language accessible to all intelligent people. I hope that this book can be read with profit both in seminars for graduate students and if the movie stinks and you forgot your sleeping pills on the businessman's special to Tokyo.