P. A. M. Dirac and the formation of the basic ideas of quantum field theory

This paper celebrates a double anniversary. In 1987, P. A. M. Dirac (1902–1984) would have been 85 years old and in addition it was 60 years ago that Dirac's paper on “The quantum theory of emission and absorption of radiation” appeared. That paper laid the foundation for modern quantum field theory. The appearance and evolution of the basic concepts and representations of quantum field theory are presented here more from a logical than a historical aspect. Special note is taken of the important role played by Dirac in this process.