Preface

Leibniz’s investigations into the structures of both natural and artificial languages, and into the impact of language use on human cognition, are widely acknowledged to have achieved real breakthroughs with respect to the standard early modern assumptions about these topics. Leibniz linked his linguistic interests with his views on mental activity by expounding the idea that language plays a fundamental role not only in communication but also in human cognition, insofar as words and signs in general serve as the indispensable thread for human thought. He used this insight into the linguistic component of thought to approach semantic phenomena such as metaphorical speech and ‘empty’ words or phrases, as well as psychological phenomena such as cognitive errors and the weakness of the will. Furthermore, his views on psycho-physical parallelism led him to explore the hypothesis that even abstract, conceptual representations have a physical counterpart in the human brain insofar as they are necessarily verbalized in a language or expressed in any other system of perceptible symbols.