Sometimes, public policy outcomes disappoint when unintended consequences arise. In many such cases, the problems might be traced back to poor reasoning. For most of antiquity, logic was considered the core element for successful human endeavour. In this work, we argue that Aristotelian logic -- specifically, the syllogism -- remains highly relevant and could offer significant benefits for the development of sound public policy. To demonstrate the value of logic for contemporary public policymaking, we first provide an accessible explanation of the practical syllogism. Following this we set out our method for testing the value of syllogistic reasoning against an example of real-world public policymaking. Thereafter, we test both the validity and truth of the apparent syllogism. We conclude that the use of a practical syllogism would have prevented unintended harm from arising in the instance under consideration and also offer our thoughts around generalisability and future research directions.