This book argues that positivism, though now the dominant paradigm for both the natural and the human sciences, is intrinsically unfit for the latter. In particular, it is unfit for linguistics and cognitive science, where it is ultimately self-destructive, since it fails to account for causality, while the mind, the primary object of research of the human sciences, cannot be understood unless considered to be an autonomous causal force.　

Author Pieter Albertus Maria Seuren, who died shortly after this manuscript was finished and after a remarkable career, reviews the history of this issue since the seventeenth century. He focuses on Descartes, Leibniz, British Empiricism and Kant, arguing that neither cognition nor language can be adequately accounted for unless the mind is given its full due. This implies that a distinction must be made—following Alexius Meinong, but against Russell and Quine—between actual and virtual reality. The latter is a product of the causally active mind and a necessary ingredient for the setting up of mental models, without which neither cognition nor language can function. Mental models are coherent sets of propositions, and can be wholly or partially true or false. Positivism rules out mental models, blocking any serious semantics and thereby reducing both language and cognition to caricatures of themselves. Seuren presents a causal theory of meaning, linking up language with cognition and solving the old question of what meaning actually amounts to.