But at what point do you lose your humanity? (Score 1)

This particular issue always reminds me of the the definition of humanity, or rather, the effor to define what makes us human. If we could see, in IR, UV, Xray, etc. would we be more or less human? How would you describe such a scene with those eyes to a person without such visual abilities? Say one person has enhanced vision, enhanced audition, strength, cognitive abilities... would this person even be able to relate to the unenhanced human? Could this person even be called human? At what point does self-engineering so remove us from where we started that we become an entirely new life-form (think Vinge's Singularity posit with a twist.) And how does one define "vision loss"? Vision less than the norm? Does a 75 year old man with 20/100 vision have vision loss, even if he is within one standard deviation of the mean for people his age? How about the person with 20/20 as compared to the person with 20/10? I see that you are a vision scientist, but for those not familiar with visual acuity testing: 20/20 is only an AVERAGE. It is not as many people will say: "perfect vision." It is not uncommon for people to have better than 20/20. Which begs the question are these folk then judged to have "vision loss" as compared to there eagle eyed bretheren? As a person in the medical field I too am interested in technology that enhances a person's quality life and more importantly may reduce suffering. But while it may be easy to define medical need by looking at a child whom has a degenerative eye disease causing blindness, the questions becomes more difficult to answer when drawn to an extreme.