It tells, from his point of view, the history of exploring atomic science and quantum mechanics in the first half of the 20th century.
As the subtitle "Encounters and Conversations" suggests, the core part of this book takes the form of discussions between himself and other scientists.
With chapters like "The first encounter with the science about atoms", "Quantum mechanics and conversations with Einstein", "Conversation about the relation between biology, physics and chemistry" or "Conversations about language" and "The behavior of an individual during a political disaster", dated 1937–1941, a reader can hear speaking such persons as Erwin Schrödinger, Niels Bohr, Albert Einstein or Max Planck, not only about physics, but also about many other questions related to biology, humans, philosophy, and politics.
Not only that, these conversations are often situated in detailed description of the historical atmosphere and a beautiful scenery, as many of them were led in nature during the many journeys they made, backpacking or sailing.
The book was published first in German 1969, in English as Physics and Beyond (1971) and in French in 1972 (La partie et le tout).