Jahoda presents the book as a work on the history of psychology but focused on aspects that most other histories choose to exclude. The purpose of it is "to provide a broad perspective of the elements of continuity and change in ideas about culture and mind during the last three centuries." She raises two essential themes in the book, on the one hand the question of what it means to be human and where the limits are between the human and the non-human; and on the other hand the question of the nature of the differences between us and the others (regarding the latter, the role played by the expansion of travel and colonial conquests in stimulating reflections on one's own culture in relation to others stands out) .