Abstract Part of the business of argumentation theory involves resolving a conceptual dispute over what argumentation and argument are in the first place. This dispute has produced various “concepts of argument.” The goal of this paper is twofold: (1) to develop a complete ontology of argumentative phenomena, capable of accounting for various conceptions of argument—something, as I argue, that is badly wanting in argumentation theory; and, within this ontology, (2) to defend a position that there is but one concept of argument needed to grasp these diverse phenomena and conceptions of argument and argumentation. I move in four steps. First, I briefly sketch the discussion over arguments-as-activities and arguments-as-products. Second, I go back to the classic work of Twardowski on actions and products and adapt it for argumentation theory, producing a complex yet systematically organized conceptual ontology of argument and argumentation. This conceptual housekeeping allows me, third, to critically engage some of the recent, Frege-inspired philosophical literature on the concept of argument, while defending act-based approaches to argument(ation). Fourth, I present a positive proposal of a minimal, contrastivist concept of argument as a set of reasons advanced to support a conclusion C 1 rather than another conclusion C n .

The article undertakes the problem of a Wittgensteinian background of Toulmin’s model of argument. While appreciating the original character of the investigations set out by Toulmin in The Uses of Argument, Wittgenstein’s ideas taken to be forerunners of both Toulmin’s philosophical method and the particular elements of the model of substantial argument are traced backward, to Toulmin’s earlier books: The Philosophy of Science (Toulmin, The philosophy of science. An introduction, Hutchinson University Library, London, 1953) and An Examination of the Place of Reason in Ethics (Toulmin, An examination of the place of reason in ethics, Cambridge University Press, Cambridge, 1950). The technique of pinpointing the constituents of that model in the books preceding The Uses of Argument is superposing the layout of Toulmin’s model on the crucial arguments concerning the earlier books: the scientific one based on Newtonian optics and the moral one concerning keeping promises. Such a procedure allows identifying backing for warrants and argument fields with the methods of representation in The Philosophy of Science and with modes of reasoning in An Examination of the Place of Reason in Ethics. The former is traced to passages 6.3 ff of Wittgenstein’s Tractatus, while the latter—to the concept of word-games (the later Wittgenstein’s language games). The claim regarding Wittgenstein’s background is that in Toulmin’s view of Wittgenstein, some parts of Tractatus concerning representing are in line with Wittgenstein’s later reflections on language games; as well as that the overall method of The Uses of Argument goes along with Wittgenstein’s therapeutic approach to philosophical problems that have to be placed in the context of their ordinary use.

In this paper I apply the epidemiological model of the spread of beliefs and how they become cultural representations to the field of fallacies. The model suggests that beliefs tend to replicate as a virus does in a potential epidemic, and those strains that are dominant in a given socio-cultural sphere become cultural representations. My ultimate aim is to denounce the fact that some presumptive argumentation schemes are widely applied as definitive arguments, but turn out to be instances of common and traditional fallacies. Moreover, some such fallacies have managed to colonise the human mind and become cultural representations in society today. Adopting the approach I advocate here, we could say that the fallacy has become a belief, which has then managed to replicate like a virus, and finally the fallacy has become a cultural representation. One of the great harms that results from this process is that it is very difficult to open up effective lines of argument that expose the fallacious nature of these new and perverse cultural representations.

Presuppositions are at the same time a crucial and almost neglected dimension of arguments and fallacies. Arguments involve different types of presuppositions, which can be used for manipulative purposes in distinct ways. However, what are presuppositions? What is their dialectical function? Why and how can they be dangerous? This paper intends to address these questions by developing the pragmatic approaches to presupposition from a dialectical perspective. The use of presuppositions will be analyzed in terms of presumptive conclusions concerning the interlocutor’s acceptance of a proposition, which can be assessed as reasonable or unacceptable. Their dialectical function is described in terms of dark side commitments attributed to a collective "voice" representing what is commonly shared. For this reason, they count as attempts to include the presupposed contents into the hearer’s commitment store, which in some circumstances can reverse the burden of proof. The different manipulative strategies grounded on controversial presuppositions will be examined by showing the distinct roles that the latter play and the relationship between the degrees of presuppositional implicitness and the speaker’s burden of retraction.