This paper deals with the problem that Alhazen formulated and solved in book V of his treatise on optics. That is to say, finding the reflection point in a given mirror, when the positions of both the object and the observer are known. The intention is to, firstly, exhibit the complex argumentation scheme used by the Arabic scientist and philosopher; and secondly, propose a possible method of reasoning like a candidate exhibiting the logic of the theory which could lead to the discovery of the solution.