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)

Besides pure declarative arguments, whose premises and conclusions are declaratives (“you sinned shamelessly; so you sinned”), and pure imperative arguments, whose premises and conclusions are imperatives (“repent quickly; so repent”), there are mixed-premise arguments, whose premises include both imperatives and declaratives (“if you sinned, repent; you sinned; so repent”), and cross-species arguments, whose premises are declaratives and whose conclusions are imperatives (“you must repent; so repent”) or vice versa (“repent; so you can repent”). I propose a general definition of argument (...) validity: an argument is valid exactly if, necessarily, every fact that sustains its premises also sustains its conclusion, where a fact sustains an imperative exactly if it favors the satisfaction over the violation of the imperative, and a fact sustains a declarative exactly if, necessarily, the declarative is true if the fact exists. I argue that this definition yields as special cases the standard definition of validity for pure declarative arguments and my previously defended definition of validity for pure imperative arguments, and that it yields intuitively acceptable results for mixed-premise and cross-species arguments. (shrink)

"Surrender; therefore, surrender or fight" is apparently an argument corresponding to an inference from an imperative to an imperative. Several philosophers, however (Williams 1963; Wedeking 1970; Harrison 1991; Hansen 2008), have denied that imperative inferences exist, arguing that (1) no such inferences occur in everyday life, (2) imperatives cannot be premises or conclusions of inferences because it makes no sense to say, for example, "since surrender" or "it follows that surrender or fight", and (3) distinct imperatives have conflicting permissive presuppositions (...) ("surrender or fight" permits you to fight without surrendering, but "surrender" does not), so issuing distinct imperatives amounts to changing one's mind and thus cannot be construed as making an inference. In response I argue inter alia that, on a reasonable understanding of 'inference', some everyday-life inferences do have imperatives as premises and conclusions, and that issuing imperatives with conflicting permissive presuppositions does not amount to changing one's mind. (shrink)

Moral emotions have been badly neglected by philosophical ethics. In my view to the detriment of this discipline because they are not only important for the moral evaluation of persons but also for value theory and thus also for a theory of morally right actions. This paper outlines my account of moral emotions. Emotions such as regret or shame are sometimes but not always moral emotions. I will determine when they are moral emotions. In I will deal with the views (...) of some other authors and in and I will explain my own account. (shrink)

This article offers a logical analysis of Slippery Slope Arguments. Such arguments claim that adopting a certain act or policy would take us down a slippery slope to an undesirable bottom and infer from this that we should refrain from this act or policy. Even though a logical assessment of such arguments has not received much careful attention, it is of vital importance to their overall assessment because if the premises fail to support the conclusion an argument is worthless. I (...) partition slippery slope reasoning by means of two dichotomies (reasoning under certainty vs. uncertainty and one-step vs. multiple-step reasoning) into four general categories and evaluate these in turn. The analysis reveals that slippery slope arguments are logically fallacious. (shrink)

In this paper my primary aim is to present a logical system of practical reasoning that can be used to assess the validity of practical arguments, that is, arguments with a practical judgment as conclusion. I begin with a critical evaluation of other approaches to this issue and argue that they are inadequate. On the basis of these considerations, I explain in Sect. 2 the informal conception of practical validity and introduce in Sect. 3 the logical system P , which (...) is an extension of propositional logic and can be used to assess the validity of a wide range of practical arguments. In the last section, I apply this system to some examples of practical reasoning in order to demonstrate how it can be used in practice. (shrink)

Robert Kimball, in “What’s Wrong with Argumentum Ad Baculum?” (Argumentation, 2006) argues that dialogue-based models of rational argumentation do not satisfactorily account for what is objectionable about more malicious uses of threats encountered in some ad baculum arguments. We review the dialogue-based approach to argumentum ad baculum, and show how it can offer more than Kimball thinks for analyzing such threat arguments and ad baculum fallacies.

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)

This article offers an analysis of normative practical reasoning. Reasoning of this type includes at least one normative belief and it has a practical conclusion (roughly, a conclusion about what to do). The principal question I am interested in is whether this type of practical reasoning can be logically conclusive. This issue has received remarkably little philosophical discussion despite the central role this reasoning plays in our everyday discourse about action and in the resolution of ethical problems. I distinguish three (...) kinds of normative reasons. Quasi -normative reasoning, I maintain in Section 1, can only be valid if it is in fact theoretical reasoning, despite appearance to the contrary. In Section 2, I argue that there are two kinds of genuine normative reasoning (purely normative reasoning and hybrid reasoning) that can be logically conclusive. This article also shows that practical arguments are non-trivially ambiguous (which has been largely ignored in the literature) because they can at the same time express different pieces of practical reasoning that have a different logical status. (shrink)