"No disagreements . Something left out ( probably because it was assumed ) , is memory . What you call mental existence I would say is a description of what causes or leads to personal identity . To me it is self evident that there is no person or personhood without a personal identity . There might be disagreement about what the particulars are concerning how to identify a personal identity , but it seems self evident to me that a mind is required , and without a brain , there is no mind , so a brain is required . It seems to me self evident that if there is no brain , there is no person . Of course , others will disagree . Some say that the unique DNA of a zygote is enough for personal identity , but if this is true , identical twins ( with identical DNA ) would have to share one personal identity , and one soul . In the case of a chimera , two souls/unique DNA in two zygotes , would have to blend into one person/soul . ( No , most chimeras are not schizophrenic ) . I believe an integral part of [ personal identity > mental existence > personhood ] is memory . Whether it is short term , or long term , without memory there is no sense of self . ( I may be stating the obvious , but you never know . ) ~ ~ ~ ~ ~ It is not clear if your list of indicators for mental existence is Â “ one will sufficeÂ ” , or Â “ several are requiredÂ ” . I donÂ ’ t think it matters all that much , but IÂ ’ m not sure , just wondering ."
"I 'm not completely sure what you mean by `` personal identity `` , but it sounds similar to what I called `` sense of self `` . It is a hard term to define . Sense of self is different than a recognition of self . I have heard that babies do not have a recognition of self - in the sense that , though they have personal experiences of pain , sensation , etc , they do not recognize themselves as separate from others - they just do n't think about their separateness so there is no recognition of a separate `` I `` . Similarly , most animals may have a sense of self - they may have a central mental center which feels the sensations , experiences the emotions , etc . - but many do not necessarily have a recognition of themselves as an `` I `` and others as `` you `` . They just do n't think about the separateness - they just have experiences that they react to . Where mental existence is concerned and criteria I use to define it , many of the criteria I listed ( thought , emotion , sense of pain , perception of experiences , sense of self , etc . ) are interdependent ( ex . emotion can be thought of as a type of thought , it takes a type of thought to recognize pain or sensation , etc. ) . However , roughly speaking , I would say that `` any of the above `` criteria would be enough to define a minimum mental existence - and thus define a person . On a last point , why is memory important to you ? Various people who have experienced major brain trauma have lost most memory function - so they have no memory of who they are , what they were doing one minute ago , etc . One can imagine that the extreme situation would be someone who has no memory at all - so he has no words to communicate , no memory of a personal history . Indeed , every experience is completely new , including the experience of pain , pleasure , etc . However , this memory-less person can still have experiences ( feel pain , pleasure , experience the input of the senses , etc. ) . He would be completely baffled as to what any experience at all is telling him , but he would still have the experiences . Extremely limited as that person would be , I would still call him a person . I 'm not sure if that is the type of memory that you were referring to . If not , then please clarify ."
"To me it is self evident that there is no person or personhood without a personal identity"
"I 'm not completely sure what you mean by `` personal identity `` , but it sounds similar to what I called `` sense of self `` . It is a hard term to define"