I'm not sure if this is appropriate but like the original author I am unsure if a CEV is a thing that can be expressed in formal logic even if he brain were fully mapped into a virtual environment. A lot of how we craft our values are based on complex environmental factors that are not easily models. Please read Schall's "Disgust embodied as moral judgement" or J Greene's fMRI Investigation of Emotional Engagement in Moral Judgement. Our values are fluid and Non-Hierarchical . Developing values that have a strict hierarchy , as the OP says can lead to systems which can not change.