Chapter 5 commences by retracing how, beginning in Nuremberg, the reasonable person entered the battlefield in the form of the reasonable military commander. Subsequently the chapter explores two challenges that confront the concept of the reasonable person on the battlefield and beyond. The first challenge consists in the fact that it is easier to empathise with people who are close to us. In the theatre of war, this raises the question whether the reasonable person, when acting as the reasonable military commander, can meaningfully balance the interests of civilians on opposite sides. The second challenge relates to the fact that it is more difficult for powerful people such as military commanders (or judges) to take the perspective of others and to empathise with them.