Editing Derek Parfit (section)

==Personal identity==
Parfit was singular in his meticulously rigorous and almost mathematical investigations into personal identity. In some cases, he used examples seemingly inspired by ''[[Star Trek]]'' and other science fiction, such as the [[teletransporter]], to explore our intuitions about our identity.<ref>{{Citation |last=Parfit |first=Derek |title=The Unimportance of Identity |date=1997 |work=Identity |pages=13–45 |editor-last=Harris |editor-first=H. |url=https://philpapers.org/rec/PARTUO |access-date=2025-02-06 |publisher=Oxford University Press}}</ref> He was a [[reductionism|reductionist]], believing that since there is no adequate criterion of personal identity, people do not exist apart from their components. Parfit argued that reality can be fully described impersonally: there need not be a determinate answer to the question "Will I continue to exist?" We could know all the facts about a person's continued existence and not be able to say whether the person has survived. He concluded that we are mistaken in assuming that personal identity is what matters in survival; what matters is rather "Relation R": psychological connectedness (namely, of memory and character) and continuity (overlapping chains of strong connectedness).<ref>{{Cite web |last=Baggini |first=Julian |date=2023-06-14 |title=Mr Morality: the astonishing mind of Derek Parfit |url=https://www.prospectmagazine.co.uk/culture/61751/mr-morality-the-astonishing-mind-of-derek-parfit |access-date=2025-01-29 |website=Prospect |language=en}}</ref>

Following [[David Hume]], Parfit argued that no unique entity, such as a self, unifies a person's experiences and dispositions over time. Therefore personal identity is not "what matters" in survival.<ref>{{Cite web|url=https://www.britannica.com/biography/Derek-Parfit|title=Derek Parfit &#124; British philosopher|website=Encyclopedia Britannica}}</ref>

A key Parfitian question is: given the choice between surviving without psychological continuity and connectedness (Relation R) and dying but preserving R through someone else's future existence, which would you choose? Parfit argues the latter is preferable.

Parfit described his loss of belief in a separate self as liberating:<ref name=":3" /><ref>{{Cite book |last=Fearn |first=Nicholas |url=https://books.google.com/books/about/The_Latest_Answers_to_the_Oldest_Questio.html?id=kXBsBnF_DVsC |title=The Latest Answers to the Oldest Questions: A Philosophical Adventure with the World's Greatest Thinkers |date=2007 |publisher=Grove Press |isbn=978-0-8021-4347-1 |pages=17 |language=en}}</ref>

{{blockquote|My life seemed like a glass tunnel, through which I was moving faster every year, and at the end of which there was darkness. When I changed my view, the walls of my glass tunnel disappeared. I now live in the open air. There is still a difference between my life and the lives of other people. But the difference is less. Other people are closer. I am less concerned about the rest of my own life, and more concerned about the lives of others.}}

===Criticism of personal identity view===
Fellow reductionist [[Mark Johnston (philosopher)|Mark Johnston]] of Princeton rejects Parfit's constitutive notion of identity with what he calls an "Argument from Above".<ref>{{cite web|author=Johnston, Mark |title=Human Concerns Without Superlative Selves |series=Dancy |year=1997 |url=http://wxy.seu.edu.cn/humanities/sociology/htmledit/uploadfile/system/20100825/20100825022102409.pdf#page=271 |url-status=dead |archive-url=https://web.archive.org/web/20120323141220/http://wxy.seu.edu.cn/humanities/sociology/htmledit/uploadfile/system/20100825/20100825022102409.pdf |archive-date=23 March 2012 |df=dmy }}</ref> Johnston maintains, "Even if the lower-level facts [that make up identity] do not in themselves matter, the higher-level fact may matter. If it does, the lower-level facts will have derived significance. They will matter, not in themselves, but because they constitute the higher level fact."<ref>{{cite web|author=Parfit, Derek|title=The Unimportance of Identity|publisher=Oxford University Press|year=1995|url=http://www.stafforini.com/txt/parfit_-_unimportance_of_identity.pdf|access-date=4 May 2011|archive-date=13 September 2016|archive-url=https://web.archive.org/web/20160913003425/http://www.stafforini.com/txt/parfit_-_unimportance_of_identity.pdf|url-status=dead}}</ref>

In this, Johnston moves to preserve the significance of personhood. Parfit's explanation is that it is not personhood itself that matters, but rather the facts in which personhood consists that provide it with significance. To illustrate this difference between himself and Johnston, Parfit used an illustration of a brain-damaged patient who becomes irreversibly unconscious. The patient is certainly still alive even though that fact is separate from the fact that his heart is still beating and other organs are still functioning. But the fact that the patient is alive is not an independent or separately obtaining fact. The patient's being alive, even though irreversibly unconscious, simply consists in the other facts. Parfit explains that from this so-called "Argument from Below" we can arbitrate the value of the heart and other organs still working without having to assign them derived significance, as Johnston's perspective would dictate.