J. Anthony Blair is a prominent international figure in argumentation studies. He is among the originators of informal logic, an author of textbooks on the informal logic approach to argument analysis and evaluation and on critical thinking, and a founder and editor of the journal Informal Logic. Blair is widely recognized among the leaders in the field for contributing formative ideas to the argumentation literature of the last few decades. This selection of key works provides insights into the history of (...) the field of argumentation theory and various related disciplines. It illuminates the central debates and presents core ideas in four main areas: Critical Thinking, Informal Logic, Argument Theory and Logic, Dialectic and Rhetoric. (shrink)

Imperatives cannot be true or false, so they are shunned by logicians. And yet imperatives can be combined by logical connectives: "kiss me and hug me" is the conjunction of "kiss me" with "hug me". This example may suggest that declarative and imperative logic are isomorphic: just as the conjunction of two declaratives is true exactly if both conjuncts are true, the conjunction of two imperatives is satisfied exactly if both conjuncts are satisfied—what more is there to say? Much more, (...) I argue. "If you love me, kiss me", a conditional imperative, mixes a declarative antecedent ("you love me") with an imperative consequent ("kiss me"); it is satisfied if you love and kiss me, violated if you love but don't kiss me, and avoided if you don't love me. So we need a logic of three -valued imperatives which mixes declaratives with imperatives. I develop such a logic. (shrink)

Why is it that most among the relatively few moral philosophers since Kant who, like J. S. Mill, have discussed the question whether there can be moral duties to oneself, have answered it negatively? One reason is that those philosophers have supposed that all moral action must be, inter alia, social; and they may have thought so because of their commitment to what is here called a 'corporationist' moral view. But such a conception of morality as social is objectionable because (...) it does not square with ordinary opinion and because it introduces an artificial division between types of action which go together in real life. (shrink)

Kant's conception of autonomy presents the following problem. If, following Kant's explicit lead, we consider autonomy as the universal principle of morality and ground of the actions of rational beings (e.g. G 4:452), then self-legislation is best understood as a prescription by reason to itself. Applied to individual cases of willing, the term 'autonomy' describes the bringing of a set of practical attitudes under rational legislation. Agents may count as autonomous then, insofar as and only to the extent that they (...) are able to implement reason's prescription. This is the bare Kantian picture. The problem, as Schiller originally put it, is that this is also a picture of self-alienation, since parts of one's identity, feelings, emotions, and attachments, are kept at arm's length and treated with suspicion (e.g. AW XXb: 280). Schiller's point is that there must be something that makes autonomy different from mere rationomy. For Schiller this matters because he thinks that a rationalist prescriptive ethic is deeply unattractive and because, anticipating contemporary theories of personal autonomy, he wants to defend an integrative conception of autonomous agency. No such further commitments are needed, however, to see that the bare picture needs adding to it, to show how the principle of reason's self-legislation not only has a grip on individual agents, but also can express their autonomy. (shrink)

Ethical theorists often assume that the verb ‘ought’ means roughly ‘has an obligation’; however, this assumption is belied by the diversity of ‘flavours’ of ought-sentences in English. A natural response is that ‘ought’ is ambiguous. However, this response is incompatible with the standard treatment of ‘ought’ by theoretical semanticists, who classify ‘ought’ as a member of the family of modal verbs, which are treated uniformly as operators. To many ethical theorists, however, this popular treatment in linguistics seems to elide an (...) important distinction between agential and non-agential ought-statements. The thought is that ‘ought’ must have at least two senses, one implicating agency and connected to obligations, and another covering other uses. In this paper, I pursue some resolution of this tension between semantic theory and ethical theory with respect to the meaning of ‘ought’. To this end, I consider what I believe to be the most linguistically sophisticated argument for the view that the word ‘ought’ is ambiguous between agential and non-agential senses. This argument, due to Mark Schroeder, is instructive but based on a false claim about the syntax of agential ought-sentences—or so I attempt to show by first situating Schroeder's argument in its proper linguistic background and then discussing some syntactic evidence that he fails to appreciate. Then, I use the failure of this argument to motivate some more general reflections on how the standard treatment of ‘ought’ by theoretical semanticists might be refined in the light of the distinction important to ethical theory between agential and non-agential ought-statements, but also on how ethical theory might benefit from more careful study of the dominant treatment of modals as operators in theoretical semantics. (shrink)

In the past couple of decades several different accounts of the logic of practical reasoning have been proposed.1 The account I have recommended on a number of occasions is clearly the simplest, because it requires no special logical principles, holding that, in respect of deduction, practical reasoning is adequately understood as involving only standard assertoric principles. My account has recently encountered various objections, the most dismissive of which is that it is too simple to deal with complicated cases of practical (...) inference. I am not daunted by these objections. My aim here is to offer some observations that will make the merits of my account easier to appreciate. (shrink)