Since Aristotle it has been common among philosophers to distinguish between two fundamental types of reasoning, theoretical and practical. We do not only want to work out what is the case but also what we ought to do. This article offers a logical analysis of instrumental reasoning, which is the paradigm of practical reasoning. In the first section I discuss the major types of instrumental reasoning and show why the accounts of most authors are defective. On the basis of this (...) discussion, I demonstrate in the second section that different types of normative conclusions are derivable from instrumental arguments and I show that it is an argument’s logical structure that determines what type of conclusion this is. (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)