practical reasoning the inferential process by which considerations for or against envisioned courses of action are brought to bear on the formation and execution of intention. The content of a piece of practical reasoning is a practical argument. Practical arguments can be complex, but they are often summarized in syllogistic form. Important issues concerning practical reasoning include how it relates to theoretical reasoning, whether it is a causal process, and how it can be evaluated. Theories of practical reasoning tend to divide into two basic categories. On one sort of view, the intrinsic features of practical reasoning exhibit little or no difference from those of theoretical reasoning. What makes practical reasoning practical is its subject matter and motivation. Hence the following could be a bona fide practical syllogism: Exercise would be good for me. Jogging is exercise. Therefore, jogging would be good for me. This argument has practical subject matter, and if made with a view toward intention formation it would be practical in motivation also. But it consists entirely of propositions, which are appropriate contents for belief-states. In principle, therefore, an agent could accept its conclusion without intending or even desiring to jog. Intention formation requires a further step. But if the content of an intention cannot be a proposition, that step could not count in itself as practical reasoning unless such reasoning can employ the contents of strictly practical mental states. Hence many philosophers call for practical syllogisms such as:
Would that I exercise.
Jogging is exercise.
Therefore, I shall go jogging. Here the first premise is optative and understood to represent the content of a desire, and the conclusion is the content of a decision or act of intention formation. These contents are not true or false, and so are not propositions.
Theories that restrict the contents of practical reasoning to propositions have the advantage that they allow such reasoning to be evaluated in terms of familiar logical principles. Those that permit the inclusion of optative content entail a need for more complex modes of evaluation. However, they bring more of the process of intention formation under the aegis of reason; also, they can be extended to cover the execution of intentions, in terms of syllogisms that terminate in volition. Both accounts must deal with cases of self-deception, in which the considerations an agent cites to justify a decision are not those from which it sprang, and cases of akrasia, where the agent views one course of action as superior, yet carries out another.
Because mental content is always abstract, it cannot in itself be a nomic cause of behavior. But the states and events to which it belongs – desires, beliefs, etc. – can count as causes, and are so treated in deterministic explanations of action. Opponents of determinism reject this step, and seek to explain action solely through the teleological or justifying force carried by mental content.
Practical syllogisms often summarize very complex thought processes, in which multiple options are considered, each with its own positive and negative aspects. Some philosophers hold that when successfully concluded, this process issues in a judgment of what action would be best all things considered – i.e., in light of all relevant considerations. Practical reasoning can be evaluated in numerous ways. Some concern the reasoning process itself: whether it is timely and duly considers the relevant alternatives, as well as whether it is well structured logically. Other concerns have to do with the products of practical reasoning. Decisions may be deemed irrational if they result in incompatible intentions, or conflict with the agent’s beliefs regarding what is possible. They may also be criticized if they conflict with the agent’s best interests. Finally, an agent’s intentions can fail to accord with standards of morality. The relationship among these ways of evaluating intentions is important to the foundations of ethics. See also ACTION THEORY, AKRASIA, INTU- ITION , PRACTITION , REASONS FOR ACTION , VOLITIO. H.J.M.