The logical problem of artificial intelligence—the question of whether the notion sometimes referred to as ‘strong’ AI is self-contradictory—is, essentially, the question of whether an artificial form of life is possible. This question has an immediately paradoxical character, which can be made explicit if we recast it (in terms that would ordinarily seem to be implied by it) as the question of whether an unnatural form of nature is possible. The present paper seeks to explain this paradoxical kind of possibility (...) by arguing that machines can share the human form of life and thus acquire human mindedness, which is to say they can be intelligent, conscious, sentient, etc. in precisely the way that a human being typically is. (shrink)

Wittgenstein’s “machines-as-symbols” are considered with respect to their historical sources and their symbolic and logical nature. Among these sources and precursors, along with Leonardo’s drawings of machines, there are illustrated “machine books”, a kind of book published in the period from the 16th to the 18th centuries which consist of pictures and descriptions of a variety of mechanical devices. Most probably, these books were one of Wittgenstein’s inspirations for his view of machines as components of language-games. The picture of homo (...) volans in Vrančić’s machine book possessed by Wittgenstein is taken as an example. In particular, homo volans is shown to contain patterns of logical laws and rules and to be abstractly interpretable as a logical symbol. A machine, taken as a symbol, is shown to be a precondition of a meaningful “overview” of a mechanical work that exceeds the limits of decidability, and to possess causal features if causality is understood teleologically and in a deeper sense of a “binding” life. (shrink)

In this paper, I offer a close reading of Wittgenstein's remarks on inconsistency, mostly as they appear in the Lectures on the Foundations of Mathematics. I focus especially on an objection to Wittgenstein's view given by Alan Turing, who attended the lectures, the so-called ‘falling bridges’-objection. Wittgenstein's position is that if contradictions arise in some practice of language, they are not necessarily fatal to that practice nor necessitate a revision of that practice. If we then assume that we have adopted (...) a paraconsistent logic, Wittgenstein's answer to Turing is that if we run into trouble building our bridge, it is either because we have made a calculation mistake or our calculus does not actually describe the phenomenon it is intended to model. The possibility of either kind of error is not particular to contradictions nor inconsistency, and thus contradictions do not have any special status as a thing to be avoided. (shrink)

Review of Kuusela, Oskari. Wittgenstein on Logic as the Method of Philosophy: Re-examining the Roots and Development of Analytic Philosophy. Oxford: Oxford University Press, 2019.

In Philosophical Investigations 193–94, Wittgenstein draws a notorious analogy between the working of a machine and the application of a rule. According to the view of rule-following that Wittgenstein is criticizing, the future applications of a rule are completely determined by the rule itself, as the movements of the machine components are completely determined by the machine configuration. On what conception of the machine is such an analogy based? In this paper, I intend to show that Wittgenstein relied on quite (...) a specific scientific tradition very active at the beginning of the twentieth century: the kinematic or the general science of machines. To explain the fundamental tenets of this line of research and its links with Wittgenstein, I focus on Franz Reuleaux, whose works were known to Wittgenstein. The first payoff of this investigation is to help distance the functionalist framework from which this passage is often read: Wittgenstein’s machines are not computers. The second payoff is to explain why Wittgenstein talks about machines at this place in his discussion on rule-following: it is not the machine model in itself that is criticized in PI 193–94, but the “philosophical” temptation to generalize from it. (shrink)

This paper reveals two fallacies in Turing's undecidability proof of first-order logic (FOL), namely, (i) an 'extensional fallacy': from the fact that a sentence is an instance of a provable FOL formula, it is inferred that a meaningful sentence is proven, and (ii) a 'fallacy of substitution': from the fact that a sentence is an instance of a provable FOL formula, it is inferred that a true sentence is proven. The first fallacy erroneously suggests that Turing's proof of the non-existence (...) of a circle-free machine that decides whether an arbitrary machine is circular proves a significant proposition. The second fallacy suggests that FOL is undecidable. (shrink)

An investigation of the concept of “surveyability” as traced through the thought of Hilbert, Wittgenstein, and Turing. The communicability and reproducibility of proof, with certainty, are seen as earmarked by the “surveyability” of symbols, sequences, and structures of proof in all these thinkers. Hilbert initiated the idea within his metamathematics, Wittgenstein took up a kind of game formalism in the 1920s and early 1930s in response. Turing carried Hilbert’s conception of the “surveyability” of proof in metamathematics through into his analysis (...) of what a formal system (what a step in a computation) is in “On computable numbers, with an application to the Entscheidungsproblem” (1936). Wittgenstein’s 1939 investigations of the significance of surveyability to the concept of “proof “in Principia Mathematica were influenced, both by Turing’s remarkable everyday analysis of the Hilbertian idea, and by conversations with Turing. Although Turing does not use the word “surveyability” explicitly, it is clear that the Hilbertian idea plays a recurrent role in his work, refracted through his engagement with Wittgenstein’s idea of a “language-game”. This is evinced in some of his later writings, where the “reform” of mathematical notation for the sake of human surveyability (1944/45) may be seen to draw out the Hilbertian idea. For Turing, as for Wittgenstein, the need for “surveyability” earmarks the evolving culture of humans located in an evolving social and scientific world, just as it had for Hilbert. (shrink)

This paper addresses the possibility of using the Wittgensteinian conception of “forms of life” (“_Lebensformen_”) as a potentially transformative philosophical framework that responds to contemporary challenges. These challenges can be understood as resulting from parallel discourses of “ends”: that of “nature” and that of the “human”. These challenges are relevant, especially, for a Cavellian interpretation of Wittgensteinian _Lebensformen_ as an expression of cultural and natural factors. My purpose is to show how Cavell’s elaboration of Wittgensteinian _Lebensformen_ can be maintained against (...) the critical pressures exerted by prevailing discourses of ends. (shrink)

L'idée de « progrès » en philosophie, ancrée dans la devise des Recherches Philosophiques, est à la fois grammaticale et autobiographique. Où se trouvait le progrès de Wittgenstein dans les années qui avaient suivi le Tractatus? Quelles leçons tirer de son parcours? Pour répondre à la question, il faut repenser la manière dont la grammaire du « progrès » doit être pesée et mesurée en philosophie. Nous nous appuyons sur l'essai de Jacques Bouveresse « Les ténèbres de notre temps (1991)» (...) et l'idée de Stanley Cavell selon laquelle la pratique philosophique de Wittgenstein dans le Tractatus et les Recherches Philosophiques s'appuient partout sur le fait de voir à travers les réalités les possibilités, traiter la « forme » comme une possibilité de la structure. Cela permet de retracer le destin de tournants de pensée apparaissant déjà dans le Tractatus : variations sur des lignes de pensée que Wittgenstein reprendra plus tard et qu’il réorchestrera d'une nouvelle manière. (shrink)

ABSTRACTZalabardo argues that the Tractatus account of picturing is a direct and successful refutation of Russell’s ‘multiple relation’ theory of judgment, its role being ontological: Wittgenstein...

In his 1939 Cambridge Lectures on the Foundations of Mathematics, Wittgenstein proclaims that he is not out to persuade anyone to change their opinions. I seek to further our understanding of this point by investigating an exchange between Wittgenstein and Turing on contradictions. In defending the claim that contradictory calculi are mathematically defective, Turing suggests that applying such a calculus would lead to disasters such as bridges falling down. In the ensuing discussion, it can seem as if Wittgenstein challenges Turing's (...) claim that such disasters would occur. I argue that this is not what Wittgenstein is doing. Rather, he is scrutinizing the meaning and philosophical import of Turing's claim—showing how Turing is wavering between making an empirical prediction and a logical observation, and that it is only through this wavering that Turing can believe that he has provided a proper explanation of why contradictory calculi are mathematically defective. (shrink)

Individual responsibility is usually articulated either in terms of an individual’s intentions or in terms of the consequences of her actions. However, many of the situations we encounter on a regular basis are structured in such a way as to render the attribution of individual responsibility unintelligible in intentional or consequential terms. Situations of this type require a different understanding of individual responsibility, which I call conditioned responsibility. The conditioned responsibility model advances that, in such situations, responsibility arises directly out (...) of the conditions in which the individual finds herself, irrespective of her intentions or of the consequences of her actions. This model gives rise to a series of challenges, some of which, I propose, can be addressed by drawing on Wittgenstein’s later notion of form of life, together with the notion of honesty implicit in his early approach to ethics. (shrink)