Fabrizio Calzavarini

Reverse inference is a crucial inferential strategy used in cognitive neuroscience to derive conclusions about the engagement of cognitive processes from patterns of brain activation. While widely employed in experimental studies, it is now viewed with increasing scepticism within the neuroscience community. One problem with reverse inference is that it is logically invalid, being an instance of abduction in Peirce’s sense. In this paper, we offer the first systematic analysis of reverse inference as a form of abductive reasoning and highlight some relevant implications for the current debate. We start by formalising an important distinction that has been entirely neglected in the literature, namely the distinction between weak and strong reverse inference. Then, we rely on case studies from recent neuroscientific research to systematically discuss the role and limits of both strong and weak reverse inference; in particular, we offer the first exploration of weak reverse inference as a discovery strategy within cognitive neuroscience.

In philosophical semantics, a distinction has been proposed between inferential and referential lexical semantic competence. The former accounts for the relationship of words to the world, the latter for the relationship of words among themselves. Recent neuroscience research suggests that the distinction might be actually neurally implemented. That is, that inferential and referential abilities might be underpinned by two functionally independent cognitive architectures, with partly different neural realizations. This hypothesis is consistent with brain patient data, supporting the notion of a functional double dissociation between inferential and referential abilities, and with neuroscience data, suggesting that inferential and referential abilities are underpinned by at least partly different regions of the human brain. The principal aim of this article is to provide the first comprehensive and critical review of the empirical evidence in favour of such hypothesis.

This monograph offers a novel, neurocognitive theory concerning words and language. It explores the distinction between inferential and referential semantic competence. The former accounts for the relationship of words among themselves, the latter for the relationship of words to the world. The author discusses this distinction at the level of the human brain on both theoretical and neuroscientific grounds. In addition, this investigation considers the relation between the inf/ref neurocognitive theory and other accounts of semantic cognition proposed in the field of neurosemantics, as well as some potential implications of the theory for clinical neuroscience and the philosophy of semantics. Overall, the book offers an important contribution to the debate about lexical semantic competence. It combines a strong philosophical and linguistic background with a comprehensive and critical analysis of neurosemantic literature. Topics discussed lie at the intersection of philosophical semantics, linguistics, neurolinguistics, cognitive science, artificial intelligence, cognitive neuroscience, and clinical psychology. Due to its interdisciplinary orientation, coverage is rich in introductory remarks and not overly technical, therefore it is accessible to non-experts as well.

Advocates of the pictorial theory of meaning claimed that the meaning of a word is a mental picture and that lexical semantic competence --i.e. knowledge of word meaning -- is closely connected to visual imagery. As a philosophical theory of meaning, the pictorial theory was discredited in the twentieth century. Nevertheless, there is evidence that visual imagery -- the generation of visual mental images -- does play a role in semantic processing and is not just a possible side effect of it. The aim of this article is to critically assess the neuroscientific status of the pictorial theory of meaning as a hypothesis about the neurocognitive underpinnings of lexical semantic competence. I will assess relevant neuroimaging, behavioural, and patient data, as well as data from congenital blindness studies.

When dealing with ‘meaning’ or related notions, one cannot ignore what for a long time was the dominant paradigm in semantics. According to such paradigm, truth-conditional formal semantics for natural language is a theory of semantic competence. In this article, I shall discuss a foundational problem for such semantic program. I shall first be following authors who claim that truth-conditional formal semantics is unable to provide a complete account of lexical competence, and, therefore, it suffers from incompleteness. Moreover, as a few authors observed, a coherent completion of lexical meaning/competence cannot be easily provided in the philosophical framework of truth-conditional semantics. The problem is a consequence of Kripke’s and Putnam’s arguments against the view that semantic values of words are cognitively determined. I shall argue that these arguments undermine the notion that formal semantics can be, at the same time, a theory of truth-conditions and a theory of semantic competence. I shall outline and critically discuss two general attempts to solve this problem, which I shall refer to as the social/ideal route and the concepts route. The conclusions of the article are deliberately open. I shall argue that both these attempts are exposed to conceptual troubles and counterintuitive consequences, and so the lexical problem still remains a deep and unresolved issue for semantics.