This book is a rich and articulate discussion on the controversial relationship between the cognitive method related to the sciences dealing with the study of complexity (human sciences) and that related to nature sciences. Scientists indeed, have always been torn by the internal conflict between an apparently exhaustive and linear theory and its uncertain practice, which falsifies and challenges the certainties of the reference models. Psychoanalysis has always been a step forward or a step back compared to science in the epistemological field and constantly in search of an organic relationship with it. The "complex thought", therefore would clarify quite different phenomena, such as those studied by nature sciences and those investigated by psychoanalysis, providing a common key to interpretation of the processes manifest in them.