Truth and falsehood for non-representationalists: Gorgias on the normativity of language

Sophists and rhetoricians like Gorgias are often accused of disregarding truth and rationality: their speeches seem to aim only at effective persuasion, and be constrained by nothing but persuasiveness itself. In his extant texts Gorgias claims that language does not represent external objects or communicate internal states, but merely generates behavioural responses in people. It has been argued that this perspective erodes the possibility of rationally assessing speeches by making persuasiveness the only norm, and persuasive power the only virtue, of speech. Against this view, I show how Gorgias’ texts support a robust normativity of language that goes well beyond persuasion while remaining non-representational. Gorgias’ claims that a speech can be persuasive and false, or true and unpersuasive, reveal pragmatic, epistemic, and agonistic constraints on the validity of speech that are neither representational nor reducible to sheer persuasiveness

Brains In Vats? Don\u27t Bother!

Contemporary discussions of epistemological skepticism – the view that we do not and cannot know anything about the world around us – focus very much on a certain kind of skeptical argument involving a skeptical scenario (a situation familiar from Descartes\u27 First Meditation). According to the argument, knowing some ordinary proposition about the world (one we usually take ourselves to know) requires knowing we are not in some such skeptical scenario SK; however, since we cannot know that we are not in SK we also cannot know any ordinary proposition. One of the most prominent skeptical scenarios is the brain-in-the-vat-scenario: An evil scientist has operated on an unsuspecting subject, removed the subject\u27s brain and put it in a vat where it is kept functioning and is connected to some computer which feeds the brain the illusion that everything is “normal”. This paper looks at one aspect of this scenario after another – envatment, disembodiment, weird cognitive processes, lack of the right kind of epistemic standing, and systematic deception. The conclusion is that none of these aspects (in isolation or in combination) is of any relevance for a would-be skeptical argument; the brain-in-the-vat-scenario is irrelevant to and useless for skeptical purposes. Given that related scenarios (e.g., involving evil demons) share the defects of the brain-in-the-vat-scenario, the skeptic should not put any hopes on Cartesian topoi

Brains in Vats? Don't Bother!

Contemporary discussions of epistemological skepticism - the view that we do not and cannot know anything about the world around us - focus very much on a certain kind of skeptical argument involving a skeptical scenario (a situation familiar from Descartes’ First Meditation). According to the argument, knowing some ordinary proposition about the world (one we usually take ourselves to know) requires knowing we are not in some such skeptical scenario SK; however, since we cannot know that we are not in SK we also cannot know any ordinary proposition. One of the most prominent skeptical scenarios is the brain-in-the-vat-scenario: An evil scientist has operated on an unsuspecting subject, removed the subject’s brain and put it in a vat where it is kept functioning and is connected to some computer which feeds the brain the illusion that everything is “normal”. This paper looks at one aspect of this scenario after another – envatment, disembodiment, weird cognitive processes, lack of the right kind of epistemic standing, and systematic deception. The conclusion is that none of these aspects (in isolation or in combination) is of any relevance for a would-be skeptical argument; the brain-in-the-vat-scenario is irrelevant to and useless for skeptical purposes. Given that related scenarios (e.g., involving evil demons) share the defects of the brain-in-the-vat-scenario, the skeptic should not put any hopes on Cartesian topoi

The Arabic Sea Battle: al-Fārābī on the Problem of Future Contingents

Ancient commentators like Ammonius and Boethius tried to solve Aristotle's “sea battle argument” in On Interpretation 9 by saying that statements about future contingents are “indefinitely” true or false. They were followed by al-Fārābī in his commentary on On Interpretation. The article sets out two possible interpretations of what “indefinitely” means here, and shows that al-Fārābī actually has both conceptions: one applied in his interpretation of Aristotle, and another that he is forced into by the problem of divine foreknowledge. It also explains the relevance of al-Fārābī's remarks as a link between the non-statistical modal theories of Philo and Avicenna

The Science of Philosophy: Discourse and Deception in Plato’s Sophist

At 252e1 to 253c9 in Plato’s Sophist, the Eleatic Visitor explains why philosophy is a science. Like the art of grammar, philosophical knowledge corresponds to a generic structure of discrete kinds and is acquired by systematic analysis of how these kinds intermingle. In the literature, the Visitor’s science is either understood as an expression of a mature and authentic platonic metaphysics, or as a sophisticated illusion staged to illustrate the seductive lure of sophistic deception. By showing how the Visitor’s account of the science of philosophy is just as comprehensive, phantasmatic and self-concealing as the art of sophistry identified at the dialogue’s outset, this paper argues in favor of the latter view

Truth-Revealing Mechanisms for Courts

In trials witnesses often slant their testimony in order to advance their own interests. To obtain truthful testimony, the law relies on cross-examination under threat of prosecution for perjury. We show that perjury law is an imperfect truth-revealing mechanism. More importantly, we develop a perfect truth-revealing mechanism. Under this mechanism the witness is sanctioned if a court eventually finds that the testimony was incorrect; the court need not determine that testimony was dishonest. We explain how truth-revealing mechanisms could combat distortions of observations by factual witnesses and exaggerations by experts, including "junk science."

A framework for Distributional Formal Semantics

Formal semantics and distributional semantics offer complementary strengths in capturing the meaning of natural language. As such, a considerable amount of research has sought to unify them, either by augmenting formal semantic systems with a distributional component, or by defining a formal system on top of distributed representations. Arriving at such a unified framework has, however, proven extremely challenging. One reason for this is that formal and distributional semantics operate on a fundamentally different `representational currency': formal semantics defines meaning in terms of models of the world, whereas distributional semantics defines meaning in terms of linguistic co-occurrence. Here, we pursue an alternative approach by deriving a vector space model that defines meaning in a distributed manner relative to formal models of the world. We will show that the resulting Distributional Formal Semantics offers probabilistic distributed representations that are also inherently compositional, and that naturally capture quantification and entailment. We moreover show that, when used as part of a neural network model, these representations allow for capturing incremental meaning construction and probabilistic inferencing. This framework thus lays the groundwork for an integrated distributional and formal approach to meaning