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Personal Identity

Only 'X' and 'Y' Principle

(Text as at 06/07/2023 00:43:12)

Plug Note¹

• Thesis Text:
  1. This principle (also known as the ‘Only X and Y Rule’, with and without various forms of quotation mark around the variables) – probably first enunciated by Harold Noonan – claims that in saying whether X is identical to Y, the existence of some other entity Z should have no bearing.
  2. The principle is averse to Closest Continuer² theories, where a “better candidate” – often in modal situations – can undermine the case of an entity to be the continuer of – that is, identical to – an earlier entity; so, “X would have been identical to Y were it not for the existence of a better candidate Z”.
  3. As such, there is some connection with supposed Contingent Identity³.
  4. I accept this principle, though this is not the case for all who clearly understand and reference it.

References

• Relevant Works cited above: No items to list.
• For a page of Links⁴ to this Note, Click here. I originally tried using ‘X and Y’ as a cognate, but it produced a lot of false positives where these variables were used for other purposes. I note those germane to my Thesis in this footnote₅.
• Works on – or which mention – this topic that I’ve actually read⁶, include the following:-
  • General:
    1. "Noonan (Harold) - Against the Closest Continuer Theory", 2003, Annotations
    2. "Noonan (Harold) - Parfit and What Matters in Survival", 2003, Annotations
    3. "Noonan (Harold) - The Reduplication Problem", 2003, Annotations
    4. "Olson (Eric) - Immanent Causation and Life After Death", 2010, Write-Up Note⁷, Annotations, External Link, Internal PDF Link
    5. "Olson (Eric) - Life After Death and the Devastation of the Grave", 2015, Annotations, External Link, Internal PDF Link
    6. "Zimmerman (Dean) - Bodily Resurrection: The Falling Elevator Model Revisited", 2010, Annotations, Internal PDF Link
• A further reading list might start with:-
  • General:
    1. "Baillie (James) - Identity and Survival", 1993
    2. "Brennan (Andrew) - Identity and Discontinuity", 1988
    3. "Corcoran (Kevin) - I'm No Soul, Man: a Response to Baltimore", 2006, Internal PDF Link
    4. "Noonan (Harold) - The Only X and Y Principle", 1985, Internal PDF Link, Read = 17%
    5. "Noonan (Harold) - The Possibility of Reincarnation", 1990, Internal PDF Link, Read = 100%

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• For a list of Works that have been considered, but have missed the cut for inclusion in this Section of my Thesis, see the following:-
  1. Read: No items to list.
  2. Further Reading: No items to list.
• This is mostly a place-holder⁸.

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In-Page Footnotes:

Footnote 5:

1. I’m not quite sure why I went to the bother of listing these, where “x and y” appears unrelated to the “Only x and y” principle.
2. But here they are!
   • Constitution, eg.
     → "Baker (Lynne Rudder) - Unity without Identity: A New Look at Material Constitution",
     → "Olson (Eric) - What Are We? Constitution", and
     → "Soames (Scott) - Kripke's Argument on Pain".
   • Leibniz Law, eg.
     → "Barnes (Kenneth) - Aristotle on Identity and Its Problems",
     → "Thomas (Janice L.) - Descartes' arguments for dualism", and
     → "Thomas (Janice L.) - Psychological continuity".
   • Relative Identity, eg.
     → "Anscombe (G.E.M.) - Objects and Identity: Foreward",
     → "Deutsch (Harry) - Relative Identity",
     → "Noonan (Harold) - Relative Identity",
     → "Olson (Eric) - What Are We? Animals",
     → "Shoemaker (David) - Personal Identity and Ethics - Conclusion: Notes on Method",
     → "Wiggins (David) - Continuants: Their Activity, Their Being, and Their Identity: Introduction", and
     → "Wiggins (David) - Identity, Individuation, and Substance".
   • Animalism, eg.
     → "Van Inwagen (Peter) - Material Beings: Preface".
   • Semantic Rules, eg.
     → "Baur (Michael) - Review of 'Kinds of Being: A Study of Individuation, Identity and the Logic of Sortal Terms' by E. J. Lowe".
   • Mereology, eg.
     → "Chisholm (Roderick) - Mereological Essentialism: Further Considerations", and
     → "Sider (Ted) - Review of Lynne Rudder Baker, Persons and Bodies".
   • Causal Overdetermination, eg.
     → "Sider (Ted) - What’s So Bad about Overdetermination?".
   • Intrinsic Properties, eg.
     → "Sider (Ted) - Intrinsic Properties".
     

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Table of the Previous 5 Versions of this Note:

Date	Length	Title
20/09/2022 11:24:00	3240	Only 'X' and 'Y' Principle
01/05/2022 18:20:10	2859	Only 'X' and 'Y' Principle
15/02/2021 13:40:48	2753	Only 'X' and 'Y' Principle
29/09/2020 11:41:17	2399	Only 'X' and 'Y' Principle
14/01/2019 21:30:14	4369	Only 'X' and 'Y' Principle

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Note last updated	Reading List for this Topic	Parent Topic
06/07/2023 00:43:12	None available	Closest Continuer

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Summary of Notes Referenced by This Note

Animalism	Awaiting Attention (Personal Identity)	Causality	Closest Continuer	Constitution
Contingent Identity	Leibniz	Mereology	Note Links Explanation	Olson - Immanent Causation and Life After Death
Plug Note Apologia	Properties	Relative Identity	Works Read - Explanation

To access information, click on one of the links in the table above.

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Summary of Notes Citing This Note

Closest Continuer, 2, 3	Existential Passage	Olson - What Are We? The Question	PID Note, Book & Paper Usage, 2, 3	Psychological Continuity - Forward
Teletransportation	Thesis - Chapter 01 (Introduction)	Thesis - Chapter 04 (Basic Metaphysical Issues), 2, 3, 4, 5, 6, 7, 8	Thesis - Chapter 10 (Thought Experiments)	Thesis - Chapter 12 (Conclusion)
Thesis - Current Stance	Thesis - Personal Identity, 2, 3, 4, 5, 6, 7	Website Generator Documentation - Auto-Reference Notes	Website Generator Documentation - Functors, 2, 3, 4, 5, 6

To access information, click on one of the links in the table above.

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Authors, Books & Papers Citing this Note

Author	Title	Medium	Extra Links	Read?
Anscombe (G.E.M.)	Objects and Identity: Foreward	Paper
Bailey (Andrew M.)	The Elimination Argument	Paper	2
Baillie (James)	Identity and Survival	Paper
Brennan (Andrew)	Identity and Discontinuity	Paper
Corcoran (Kevin)	I'm No Soul, Man: a Response to Baltimore	Paper
Hanley (Richard)	The Metaphysics of Star Trek: To Beam or Not to Beam?	Paper		Yes
Hershenov (David)	Animals, Persons and Bioethics	Paper
Noonan (Harold)	Against the Closest Continuer Theory	Paper		Yes
Noonan (Harold)	Parfit and What Matters in Survival	Paper		Yes
Noonan (Harold)	The Only X and Y Principle	Paper
Noonan (Harold)	The Possibility of Reincarnation	Paper	2, 3, 4
Noonan (Harold)	The Reduplication Problem	Paper	2	Yes
Noonan (Harold)	Wiggins, Artifact Identity and 'Best Candidate' Theories	Paper	2, 3, 4
Olson (Eric)	Life After Death and the Devastation of the Grave	Paper		Yes
Olson (Eric)	What Are We? The Question	Paper		Yes
Todman (Theo)	Thesis - Chapter 01 (Introduction)	Paper		Yes
Todman (Theo)	Thesis - Chapter 04 (Basic Metaphysical Issues)	Paper	2, 3, 4, 5, 6, 7, 8	Yes
Todman (Theo)	Thesis - Chapter 10 (Thought Experiments)	Paper		Yes
Todman (Theo)	Thesis - Chapter 12 (Conclusion)	Paper		Yes
Todman (Theo)	Thesis - Closest Continuer	Paper	2, 3	Yes
Todman (Theo)	Thesis - Current Position	Paper		Yes
Todman (Theo)	Thesis - Personal Identity	Paper	2, 3, 4, 5, 6, 7	Yes
Todman (Theo)	Thesis - Psychological Continuity - Forward	Paper		Yes
Todman (Theo)	Thesis - Teletransportation	Paper		Yes
Zimmerman (Dean)	Bodily Resurrection: The Falling Elevator Model Revisited	Paper	2, 3, 4	Yes

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References & Reading List

Author	Title	Medium	Source	Read?
Anscombe (G.E.M.)	Objects and Identity: Foreward	Paper - Cited	Noonan - Objects and Identity, 1980, Foreward	No
Baillie (James)	Identity and Survival	Paper - Cited	Baillie (James) - Problems in Personal Identity, 1993, Chapter 2	No
Baillie (James)	Problems in Personal Identity	Book - Cited (via Paper Cited)	Bibliographical details to be supplied	45%
Baker (Lynne Rudder)	Unity without Identity: A New Look at Material Constitution	Paper - Cited	Midwest Studies In Philosophy, 1999, Vol. XXIII Issue 1, p144, 22p	Yes
Barnes (Kenneth)	Aristotle on Identity and Its Problems	Paper - Cited	Phronesis, Vol. 22, No. 1 (1977), pp. 48-62	No
Baur (Michael)	Review of 'Kinds of Being: A Study of Individuation, Identity and the Logic of Sortal Terms' by E. J. Lowe	Paper - Cited	The Review of Metaphysics, Vol. 46, No. 1 (Sep., 1992), pp. 166-168	Yes
Brennan (Andrew)	Conditions of Identity	Book - Cited (via Paper Cited)	Bibliographical details to be supplied	0%
Brennan (Andrew)	Identity and Discontinuity	Paper - Cited	Brennan - Conditions of Identity, 1988, Chapter 4	No
Chisholm (Roderick)	Mereological Essentialism: Further Considerations	Paper - Cited	Review of Metaphysics 28, 1975, pp. 477–484	No
Corcoran (Kevin)	I'm No Soul, Man: a Response to Baltimore	Paper - Cited	Religious Studies, Volume 42, Issue 04, December 2006, pp 431-437	No
Deutsch (Harry)	Relative Identity	Paper - Cited	Stanford Encyclopaedia of Philosophy, 2002-7	4%
French (Peter) & Wettstein (Howard), Eds.	Midwest Studies in Philosophy (Vol XXIII) - New Directions in Philosophy	Book - Cited (via Paper Cited)	Bibliographical details to be supplied	9%
Gasser (Georg), Ed.	Personal Identity and Resurrection: How Do We Survive Our Death?	Book - Cited (via Paper Cited)	Bibliographical details to be supplied	96%
Hale (Bob) & Wright (Crispin), Eds.	A Companion to the Philosophy of Language	Book - Cited (via Paper Cited)	Bibliographical details to be supplied	4%
Hanley (Richard)	The Metaphysics of Star Trek	Book - Referencing (via Paper Referencing)	Bibliographical details to be supplied	52%
Hanley (Richard)	The Metaphysics of Star Trek: To Beam or Not to Beam?	Paper - Referencing	Hanley (Richard) - The Metaphysics of Star Trek, Chapter 4	Yes
Martin (L. Michael) & Augustine (Keith)	The Myth of an Afterlife: The Case against Life After Death	Book - Cited (via Paper Cited)	Bibliographical details to be supplied	15%
Martin (L. Michael) & Augustine (Keith)	The Myth of an Afterlife: The Case against Life After Death	Book - Referencing (via Paper Referencing)	Bibliographical details to be supplied	15%
Noonan (Harold)	Against the Closest Continuer Theory	Paper - Cited	Noonan - Personal Identity, 2003, Chapter 12	Yes
Noonan (Harold)	Objects and Identity: An Examination of Relative Identity and its Consequences	Book - Cited (via Paper Cited)	Bibliographical details to be supplied	10%
Noonan (Harold)	Parfit and What Matters in Survival	Paper - Cited	Noonan - Personal Identity, 2003, Chapter 9	Yes
Noonan (Harold)	Personal Identity	Book - Cited (via Paper Cited)	Bibliographical details to be supplied	Yes
Noonan (Harold)	Relative Identity	Paper - Cited	Hale & Wright - A Companion to the Philosophy of Language	50%
Noonan (Harold)	The Only X and Y Principle	Paper - Cited	Analysis 45, 1985, 79-83	17%
Noonan (Harold)	The Reduplication Problem	Paper - Cited	Noonan - Personal Identity, 2003, Chapter 7	Yes
Olson (Eric)	Immanent Causation and Life After Death	Paper - Cited	Gasser (Georg) - Personal Identity and Resurrection: How Do We Survive Our Death? 2010	Yes
Olson (Eric)	Life After Death and the Devastation of the Grave	Paper - Cited	Martin & Augustine - The Myth of an Afterlife, Part 2, Chapter 19, 2015: 409-423	Yes
Olson (Eric)	Life After Death and the Devastation of the Grave	Paper - Referencing	Martin & Augustine - The Myth of an Afterlife, Part 2, Chapter 19, 2015: 409-423	Yes
Olson (Eric)	What are We? A Study of Personal Ontology	Book - Cited (via Paper Cited)	Bibliographical details to be supplied	Yes
Olson (Eric)	What are We? A Study of Personal Ontology	Book - Referencing (via Paper Referencing)	Bibliographical details to be supplied	Yes
Olson (Eric)	What Are We? Animals	Paper - Cited	What Are We? A Study in Personal Ontology, Chapter 2 (November 2007: Oxford University Press.)	Yes
Olson (Eric)	What Are We? Constitution	Paper - Cited	What Are We? A Study in Personal Ontology, Chapter 3 (November 2007: Oxford University Press.)	Yes
Olson (Eric)	What Are We? The Question	Paper - Referencing	What Are We? A Study in Personal Ontology, Chapter 1 (November 2007: Oxford University Press.)	Yes
Shoemaker (David)	Personal Identity and Ethics - Conclusion: Notes on Method	Paper - Cited	Shoemaker (David) - Personal Identity and Ethics: A Brief Introduction, 2009, Conclusion	Yes
Shoemaker (David)	Personal Identity and Ethics: A Brief Introduction	Book - Cited (via Paper Cited)	Bibliographical details to be supplied	Yes
Sider (Ted)	Intrinsic Properties	Paper - Cited	Philosophical Studies, Vol. 83, No. 1 (Jul., 1996), pp. 1-27	4%
Sider (Ted)	Review of Lynne Rudder Baker, Persons and Bodies	Paper - Cited	Journal of Philosophy 99 (2002): 45-48	Yes
Sider (Ted)	What’s So Bad about Overdetermination?	Paper - Cited	Philosophy and Phenomenological Research 67, 2003, 719-726	No
Soames (Scott)	Kripke's Argument on Pain	Paper - Cited	Center for Consciousness Studies, Moscow State University Website	56%
Soames (Scott)	Round-table with Scott Soames on Kripke's Argument on Pain	Book - Cited (via Paper Cited)	Bibliographical details to be supplied	83%
Thomas (Janice L.)	Descartes' arguments for dualism	Paper - Cited	Thomas (Janice L.) - Mind and Person in the Philosophy of Religion	Yes
Thomas (Janice L.)	Mind and Person in the Philosophy of Religion	Book - Cited (via Paper Cited)	Bibliographical details to be supplied	Yes
Thomas (Janice L.)	Psychological continuity	Paper - Cited	Thomas (Janice L.) - Mind and Person in the Philosophy of Religion	Yes
Todman (Theo)	Thesis - Chapter 04 (Basic Metaphysical Issues)	Paper - Referencing		Yes
Todman (Theo)	Thesis - Closest Continuer	Paper - Referencing		Yes
Van Inwagen (Peter)	Material Beings	Book - Cited (via Paper Cited)	Bibliographical details to be supplied	27%
Van Inwagen (Peter)	Material Beings: Preface	Paper - Cited	Van Inwagen - Material Beings, Preface	Yes
Wiggins (David)	Continuants: Their Activity, Their Being, and Their Identity	Book - Cited (via Paper Cited)	Bibliographical details to be supplied	14%
Wiggins (David)	Continuants: Their Activity, Their Being, and Their Identity: Introduction	Paper - Cited	Wiggins (David) - Continuants: Their Activity, Their Being, and Their Identity	Yes
Wiggins (David)	Identity, Individuation, and Substance	Paper - Cited	Wiggins (David) - Continuants: Their Activity, Their Being, and Their Identity	63%
Zimmerman (Dean)	Bodily Resurrection: The Falling Elevator Model Revisited	Paper - Cited	Gasser (Georg) - Personal Identity and Resurrection: How Do We Survive Our Death? 2010	Yes

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Text Colour Conventions

1. Blue: Text by me; © Theo Todman, 2026

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