This book is considered to be one of the most outstanding essays ever written on the logical possibilities and difficulties of a science of society. Considerations on the method to follow in the different areas of the social sciences are offered. In his introduction, J. Francisco Álvarez points out the continued applicability of Stuart Mill’s thought while stressing his moral impulse as champion of freedom and equality. In this book sets out Mill’s concept of ethology as the science of human character in the widest sense of the term (including the formation of individual and national or collective characters.