Wilder Penfield has enjoyed a long and fruitful career as a neurosurgeon. He began in the neurophysiological laboratory of Sherrington at Oxford and continued in the wards and operating rooms of the Montreal Neurological Institute which he founded. In the present volume, Penfield, now in his seventies, looks back over his lifetime of scientific research and applies his discoveries to answer the basic questions with which it was begun. He offers a retrospective of his pioneering discoveries of the functions of the human brain. These discoveries are fundamental to our understanding of the physical basis of memory, learning, language and behavior. Penfield describes the forces which influenced the direction of his professional career, “Preoccupations were many and varied but beneath them all was the sense of wonder and a profound curiosity about the mind. My planned objective, as I turned from studying