Any mention of linguistic universals means the continuation of a journey begun many years ago, and refers to a topic of debate among both linguists and philosophers, which has been a constant in the history of linguistics throughout the ages.

The debate regarding universals is one of the most fundamental chapters – perhaps the most fundamental – in the history of grammar, and its genesis can be traced back to the very dawn of linguistic reflection. Furthermore, it is a subject that transcends boundaries between academic disciplines since it is one of the cornerstones of the philosophical debate between rationalism and empiricism. Consequently, it is of vital interest not only to linguists, but also to philosophers, psychologists, anthropologists, psychobiologists, and ethnologists – in other words, to researchers of all academic disciplines that are involved in what is known today as Cognitive Science.

However, linguistic universals are currently in the limelight because any linguistic theory that aspires to explanatory adequacy must offer a satisfactory answer to the question of why languages that are so apparently different on the surface at the same time present undeniable regularities in their underlying structure. It is no longer a question of merely discussing the existence of universals, but rather of making their existence compatible with the epistemological premises of different theoretical approaches. This book is an explanation of how these approaches have dealt with this task.