I don't disagree with that analysis, but I believe you have reversed the terms which describe our feelings witnessing or imagining the act. The thought of hacking someone to pieces alone brings emotions of horror and disgust to my mind (shiversssssss) Ask yourself could you really place yourself in the shoes of a criminally insane person, IOW, experience their emotions of elation while they commit what they consider an act of artistry? Can you emotionally experience that state of insanity? I doubt that, I should hope not. However, we can logically come to the conclusion that a criminally insane person is incurably mentally ill and a persistent danger to the community, because he is not capable of sympathy (feeling sorry) or empathy (experiencing their pain) for his victims. A criminally insane person doesn't feel anything for his victims, he delights in their exquisite misery. He identifies his victim as an object, not a person. In the case of hostage takers, negotiators always begin by identifying the hostage by name. A name bestows personhood, and is often effective in bringing an enraged person back to reality. But a criminally insane person is never enraged, on the contrary he is proud and experiences satisfaction from admiring his work. Feeling sorry is being sympathetic , not empathic. We don't lock them away permanently from our feelings of empathy with his condition, but from our feelings of sympathy for his condition. Let's put it in a less stark context. Autism is considered a sign of a defective mirroring system, which makes then unable to empathize, or in general interact (learning to imitate) normally with other people. Could you feel empathy, i.e. walk in the shoes of an autistic person, or would you feel sympathetic to his condition? It would seem mentally impossible to actually be empathetic to being autistic and vice versa.