The book is a description of some dramatic moments in the life of science and their philosophical interpretation. Addressing priority problems, extraordinary episodes of academic life brings a personal aspect to understanding the nature of knowledge. "Borderline situations," borrowing existentialist terminology, characterize the paradigms of science no less than its "normal" development in the sense of T. Kuhn. Instead of dull textbook, often erroneous stories of the very recent past, the book presents fresh views of prominent thinkers about the nature of science and the scientific community.