The practical syllogism is an instance of practical reasoning which takes the form of a syllogism, where the conclusion of the syllogism is an action.

Aristotle discusses the notion of the practical syllogism within his treatise on ethics, his Nicomachean Ethics. A syllogism is a three-proposition argument consisting of a major premise stating some universal truth, a minor premise stating some particular truth, and a conclusion derived from these two premises. The practical syllogism is a form of practical reasoning in syllogistic form, the conclusion of which is an action. An example might be that the major premise food cures hunger and the minor premise I am hungry leads to the practical conclusion of eating food. Note that the conclusion here is not a third proposition, like I will eat, or the occurrence of an utterance like "I will eat," but is simply the act of eating. For this reason, practical syllogisms are only called syllogisms analogically. Since they do not consist of at least three propositions, they are not syllogisms properly speaking.

The theoretical reason gives no commands. The practical reason operates in the form of a practical syllogism, whose conclusion is epitactic or imperative.

Aristotle describes this syllogism as follows: All deliberate action is resolvable into a major and minor premise, from which the given action logically issues. The major premise is a general conception or moral maxim; the minor premise is a particular instance: and the conclusion is an action involved in subsuming the particular instance under the general conception or law. The conclusion is not an abstraction, as in the case of a theoretical syllogism, but consists in an action and is jussive, e.g.

Major premise: All men should take exercise;

Minor premise: I am a man;

Conclusion: I should take exercise;

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