This paper presents a rationale for doing philosophy with children. It suggests a rationale that differs from more usual arguments supporting philosophy with children—for such reasons as that it will enhance problem solving-skills or will help pupils' thinking to be more logical. These worthy objectives are not denied but only considered somewhat subordinate to the rationale proposed. This is presented in three steps. In the first step the issue of whether philosophy should be done with children is considered in the context of claims that children may be too young to do philosophy or too inexperienced in the ways of academic discipline to be able to discern proper philosophy. These objections are weighty enough, especially in view of general teacher reluctance to engage with philosophy itself in any form. In the second part, I invoke the common sense philosophy of Thomas Reid as a method of philosophy particularly significant for, and appropriate to, philosophy for children. Finally, I show how these aspects arising out of my understanding of Reid's philosophy can help resolve at least some of the misgivings people have about doing philosophy with children. It is hoped that these discussions will illuminate the question of how it may be appropriate for children to do philosophy in classrooms today.