Editing Time (section)

=== Unreality ===
In 5th century BC [[Greece]], [[Antiphon (orator)|Antiphon]] the [[Sophist]], in a fragment preserved from his chief work ''On Truth'', held that: "Time is not a reality (hypostasis), but a concept (noêma) or a measure (metron)." [[Parmenides]] went further, maintaining that time, motion, and change were illusions, leading to the [[Zeno's paradoxes|paradoxes]] of his follower [[Zeno of Elea|Zeno]].<ref>{{cite web |author=Foundalis |first=Harry |title=You are about to disappear |url=http://www.foundalis.com/phi/WhyTimeFlows.htm |url-status=live |archive-url=https://web.archive.org/web/20110512072013/http://www.foundalis.com/phi/WhyTimeFlows.htm |archive-date=12 May 2011 |access-date=9 April 2011}}</ref> Time as an illusion is also a common theme in [[Buddhism|Buddhist]] thought.<ref>{{cite web |title=Buddhism and the illusion of time |url=http://www.buddhasvillage.com/teachings/time.htm |first=Tom |last=Huston |access-date=9 April 2011 |url-status=live |archive-url=https://web.archive.org/web/20110708103214/http://www.buddhasvillage.com/teachings/time.htm |archive-date=8 July 2011  }}</ref><ref>{{cite book |url=https://books.google.com/books?id=kfsyfoO1IlYC&pg=RA1-PR19 |last=Garfield |first=Jay L. |title=The fundamental wisdom of the middle way: Nāgārjuna's Mūlamadhyamakakārikā |date=1995 |publisher=Oxford University Press |location=New York |isbn=978-0-19-509336-0 |access-date=19 May 2018 |archive-date=19 August 2020 |archive-url=https://web.archive.org/web/20200819134845/https://books.google.com/books?id=kfsyfoO1IlYC&pg=RA1-PR19 |url-status=live }}</ref>

These arguments often center on what it means for something to be ''unreal''. Modern physicists generally believe that time is as ''real'' as space—though others, such as [[Julian Barbour]], argue quantum equations of the universe take their true form when expressed in the timeless [[Configuration space (physics)|realm]] containing every possible ''now'' or momentary configuration of the universe.<ref>{{Cite web |last=Folger |first=Tim |date=30 November 2000 |title=From Here to Eternity |url=https://www.discovermagazine.com/the-sciences/from-here-to-eternity-02 |access-date=2025-02-26 |website=Discover Magazine |language=en}}</ref> [[J. M. E. McTaggart]]'s 1908 article ''[[The Unreality of Time]]'' argues that, since every event has the characteristic of being both present and not present (i.e., future or past), that time is a self-contradictory idea.

Another modern philosophical theory called [[Philosophical presentism|presentism]] views the past and the future as human-mind interpretations of movement instead of real parts of time (or "dimensions") which coexist with the present. This theory rejects the existence of all direct interaction with the past or the future, holding only the present as tangible. This is one of the philosophical arguments against time travel.<ref>{{Cite journal |last=Sakon |first=Takeshi |date=2020 |title=Presentists Should Not Believe in Time Travel |url=https://www.jstage.jst.go.jp/article/jpssj/53/2/53_191/_pdf |journal=Philosophy of Science |volume=53 |issue=2 |via=Osaka City University}}</ref> This contrasts with [[eternalism (philosophy of time)|eternalism]] (all time: present, past and future, is real) and the [[Growing block universe|growing block theory]] (the present and the past are real, but the future is not).