The departure point of this paper is the experience done by those nations who suffered barbarian catastrophes that still require to be thought. In fact, memory of particular individuals who suffered brings often in contradiction the official history, so their stories should be taken into account in order to understand the contexts that produce war and such disasters. This is the reason why History has recently tried to make room to the experience of victims, the war survivors, and has defined itself more as an exercise of memory. Somehow, all humans have been affected by such violence and cannot escape from it by living in indifference. Adorno asks the survivors to assume what he calls the negative dialectics, that is the self-reflection of thought which «means thinking against himself». He interpreted the expression as the obligation to attend to the violence that was inflicted to all humanity in the particular individuals directly involved: the executioners and their victims. This paper reflects on the relation between ethics and reflection guided by Adorno’s philosophy and tries to answer the following question: How can an ethical proposal be derived from the encounter with the memory?