You're obfuscating the point and I think it's intentional. You are skating around absolutes. I am not required to remember all of my past experiences to retain what can properly be identified as me, but I cannot be without those experiences. Those experiences inform my future actions even if that which I am able to recall are hazy imperfect facsimiles of actual events. The fact that I may not remember a majority of what I have experienced does not delegitimize what it is I do recall or make insignificant forgotten events and the impact on my present personality. The intent with which you use 'majority' here is what cautions me as to your motives. The underlying assertion that there can be no 'I' unless I can recall >50% of my past experiences is ludicrous.
As far as people suffering brain injuries and their personhood, I can only answer based on my personal experience. My mother has suffered Alzheimer's. For her sake, she completely succumbed relatively quickly. Her gradual disappearance was painful to experience, despite how fast we were told it was compared to others. I can definitively say that there is a human body that has a remarkable resemblance to my mother, but my mother no longer exists. Redefining personhood for the convenience of argument won't change this fact.
By the way, you didn't answer my question.
As far as people suffering brain injuries and their personhood, I can only answer based on my personal experience. My mother has suffered Alzheimer's. For her sake, she completely succumbed relatively quickly. Her gradual disappearance was painful to experience, despite how fast we were told it was compared to others. I can definitively say that there is a human body that has a remarkable resemblance to my mother, but my mother no longer exists. Redefining personhood for the convenience of argument won't change this fact.
By the way, you didn't answer my question.
