Theo Todman's Web Page - Notes Pages

Personal Identity

Commissurotomy

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

Plug Note¹

• Thesis Text:
  1. A commissurotomy involves cutting the corpus callosum, the bundle of nerve fibres connecting the two cerebral hemispheres² of the brain³. The procedure is used to treat epilepsy, but is invoked by philosophers as a Thought Experiment⁴ (TE) to provide an alleged real-life example of Fission⁵. The real-life situation usually has to be improved upon to overcome the laterality of the brain, and the two hemispheres are assumed to be idempotent, with nothing of philosophical significance alleged to ride on this idealisation.
  2. As with all TEs⁶, what we can learn from this one depends on our level of description of what is supposed to be going on. The idea is that each hemisphere fully supports the mental life of the subject(s), and consequently that there are, or can come to be, multiple subjects (Selves⁷) – and hence multiple persons⁸ – within the same human animal⁹.
  3. Commissurotomy is therefore used as an objection¹⁰ to animalism¹¹. Some philosophers argue that (for modal¹² reasons) there are always two Persons¹³ within the same Human Being¹⁴.
  4. Clearly, this is not obviously the case in the normal asymmetric brain¹⁵. See, no doubt, "Kinsbourne (Marcel) - Asymmetrical Function of the Brain", though this is rather an old book. So, in these Thought Experiments¹⁶ – and prior to this idealised idempotency – there has to be a period of equalisation and duplication¹⁷ of function. This sounds like it would lead to causal over-determination, but maybe the way it could be described is as with fault-tolerant computer¹⁸ systems, so that one hemisphere always takes the lead (or maybe they alternate) – in fact, this is said to be the case with marine mammals, to enable them to sleep¹⁹ without drowning: see, for instance, "Hecker (Bruce) - How do Whales and Dolphins Sleep Without Drowning?". The non-dominant hemisphere is just kept up to date – either continuously or periodically – with whatever data and current state is represented in the dominant hemisphere. In such a situation, there are already – prior to the commissurotomy – two exactly similar (other than that they are mirror images of one another) but non-identical half-brains²⁰.
  5. Of course, the last sentence above begs some questions. It is only the cerebral hemispheres²¹ that are separated and duplicated²² – but they are still physically connected via the brain-stem – even if the logical connections are greatly reduced. It is said – see "Rosen (Victoria) - One Brain. Two Minds? Many Questions" and the references therein, which summarises the controversy between Yair Pinto and Michael S. Gazzaniga – that severed hemispheres can still communicate with one another via cues passed externally to the brain²³. Indeed, the case of the dicephalus²⁴ suggests that this co-ordination is possible with two complete brains, where the hands can be coordinated to drive a car and even type, despite being controlled by different brains.
  6. A recent paper – "Pinto (Yair) - When you split the brain, do you split the person?" – has suggested that the research for which Sperry received a Nobel Prize has not been replicated²⁵ – in the case of two patients – and that this raises questions about the nature of consciousness²⁶. I have my doubts. Might the corpus collosum not have been entirely severed in these cases, or might one of the above situations apply? Rosen claims that Yair Pinto thinks that other fibers are involved.

References

• Relevant Works cited above:
  1. "Hecker (Bruce) - How do Whales and Dolphins Sleep Without Drowning?", External Link, Read
  2. "Kinsbourne (Marcel) - Asymmetrical Function of the Brain", 1978, Book
  3. "Pinto (Yair) - When you split the brain, do you split the person?", 2017, No Abstract, External Link, Internal PDF Link, Read
  4. "Rosen (Victoria) - One Brain. Two Minds? Many Questions", 2018, External Link, Internal PDF Link, Read = 100%
• For a Page of Links²⁷ to this Note, Click here.
• Works on this topic that I’ve actually read²⁸, include the following:-
  • Aeon:
    1. "Pinto (Yair) - When you split the brain, do you split the person?", 2017, No Abstract, External Link, Internal PDF Link
  • General:
    1. "Benson (Ophelia) - This Isn't My Body", 2005, External Link
    2. "Hecker (Bruce) - How do Whales and Dolphins Sleep Without Drowning?", External Link
    3. "Liao (S. Matthew) - The Organism View Defended", 2006, Annotations, Internal PDF Link, Footnote₂₉
    4. "Marks (Charles) - Commissurotomy, Consciousness and Unity of Mind", 1981, Book
    5. "Olson (Eric) - Why We Need Not Accept the Psychological Approach", 1999
    6. "Parkin (Alan) - The Split Brain", 1996
    7. "Shoemaker (David) - Personal Identity and Immortality", 2009
    8. "Van Inwagen (Peter) - Précis of Material Beings", 1993, Annotations, Internal PDF Link
    9. "Van Inwagen (Peter) - Two Problems About Personal Identity: Memory and Commissurotomy", 1990, Annotations, No Abstract
    10. "Wilkes (Kathleen) - Being in Two Minds", 2003
• A further reading list might start with:-
  • General:
    1. "Anderson (Robert M.) & Gonsalves (Joseph F.) - Sensory Suppression and the Unity of Consciousness", 1981, No Abstract
    2. "Baillie (James) - Commissurotomy and the Unity of Mind", 1993
    3. "Bogen (James) - Further discussion on split-brains and hemispheric capabilities", 1977, Internal PDF Link
    4. "Bogen (Joseph E.) - Mental Numerosity: Is One Head Better Than Two?", 1981, No Abstract
    5. "Bradshaw (John L.) - In Two Minds", 1981, No Abstract
    6. "Brown (Jason) - Structural Levels and Mental Unity", 1981, No Abstract
    7. "Churchland (Patricia) - How Many Angels … ?", 1981, No Abstract
    8. "Davidson (Richard) - Cognitive Processing Is Not Equivalent To Conscious Processing", 1981, No Abstract
    9. "Davis (Lawrence H.) - Cerebral Hemispheres", 1997
    10. "Dewitt (Larry W.) - Consciousness, Mind, and Self: The Implications of the Split-Brain Studies", 1975, Internal PDF Link
    11. "Eccles (John) - Mental Dualism and Commissurotomy", 1981, No Abstract
    12. "Gazzaniga (Michael S.) - The Split Brain Revisited", 1999, No Abstract, Internal PDF Link, Footnote₃₀
    13. "Gazzaniga (Michael S.) - The split-brain - Rooting consciousness in biology", 2014, Internal PDF Link, Read = 33%
    14. "Geschwind (Norman) - The Perverseness of the Right Hemisphere", 1981, No Abstract
    15. "Gillett (Grant) - Brain Bisection and Personal Identity", 1986, Internal PDF Link, Read = 17%
    16. "Glover (Jonathan) - Split Brains", 1988
    17. "Green (Michael) - May We Forget Our Minds For a Moment?", 1981, No Abstract
    18. "Greenwood (John) - Split-Brains and Singular Personhood", 1993
    19. "Hershenov (David) & Taylor (Adam P.) - Split Brains: No Headache for the Soul Theorist", 2014, External Link, Internal PDF Link, Read = 5%
    20. "Hirsch (Eli) - Divided Minds", 1991, Internal PDF Link
    21. "Iredale (Mathew) - Your Two Brains", 2009, No Abstract, Internal PDF Link, Read = 67%
    22. "Joynt (Robert J.) - Are Two Heads Better Than One?", 1981, No Abstract
    23. "Kinsbourne (Marcel) - Asymmetrical Function of the Brain", 1978, Book
    24. "LeDoux (Joseph E.) & Gazzaniga (Michael S.) - The Brain and the Split Brain: A Duel With Duality As a Model of Mind", 1981, No Abstract
    25. "MacKay (Donald) - Divided Brains - Divided Minds", 1989, No Abstract
    26. "Marks (Charles) - Mental Duality: An Unmade Case", 1981, No Abstract
    27. "Puccetti (Roland) - Brain Bisection and Personal Identity", 1973, Internal PDF Link
    28. "Puccetti (Roland) - Mind with a Double Brain", 1993, Internal PDF Link
    29. "Puccetti (Roland) - Multiple Identity", 1973
    30. "Puccetti (Roland) - The Case For Mental Duality: Author's Responses + References", 1981
    31. "Puccetti (Roland) - The Case For Mental Duality: Evidence From Split-Brain Data and Other Considerations", 1981, No Abstract
    32. "Puccetti (Roland) - The Mute Self: A Reaction to Dewitt's Alternative Account of the Split-Brain Data", 1976, Internal PDF Link
    33. "Puccetti (Roland) - Two Brains, Two Minds? Wigan's Theory of Mental Duality", 1989, Internal PDF Link
    34. "Rigterink (Roger J.) - Puccetti and Brain Bisection: An Attempt at Mental Division", 1980, No Abstract
    35. "Robinson (Denis) - Neurometaphorology: The New Faculty Psychology", 1981, No Abstract
    36. "Rosen (Victoria) - One Brain. Two Minds? Many Questions", 2018, External Link, Internal PDF Link, Read = 100%
    37. "Sperry (Roger W.) - Hemisphere Deconnection and the Unity in Conscious Awareness", 1968, Read = 11%
    38. "Sperry (Roger W.) - Some Effects of Disconnecting the Cerebral Hemispheres", 1982, Annotations, Internal PDF Link, Read = 117%
    39. "Thornton (Mark) - Double Brain, Double Person?", 1994, Internal PDF Link
    40. "Tye (Michael) - Split Brains", 2003
    41. "Von Eckardt (Barbara) - Puccetti's Mental-Duality Thesis: A Case Of Bad Arguments", 1981, No Abstract
    42. "Weinstein (Edwin A.) - Extinction and Hemi-Inattention: Their Relation to Commissurotomy", 1981, No Abstract
    43. "Wilkes (Kathleen) - Consciousness and Commissurotomy", 1978
    44. "Wilkes (Kathleen) - Unfused Homunculi", 1981, No Abstract

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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-holder³¹.

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In-Page Footnotes:

Footnote 29:

• Section 3 deals with Commissurotomy.
• The whole paper is interesting in defending animalism against objections.

Footnote 30:

• There are other papers on this topic by Michael S. Gazzaniga that I’ve not had time to collect yet.

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Table of the Previous 9 Versions of this Note:

Date	Length	Title
20/09/2022 11:24:00	6414	Commissurotomy
15/05/2022 13:19:12	6033	Commissurotomy
09/02/2021 00:40:19	5738	Commissurotomy
15/09/2020 13:32:10	4402	Commissurotomy
24/06/2018 16:32:10	5981	Commissurotomy
14/10/2017 23:22:34	4165	Commissurotomy
25/08/2009 15:04:19	2660	Commissurotomy
26/11/2007 23:25:26	628	Commissurotomy
12/08/2007 10:17:46	80	Commissurotomy

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Note last updated	Reading List for this Topic	Parent Topic
06/07/2023 00:43:12	Commissurotomy	Fission

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Summary of Notes Referenced by This Note

Animalism	Animalism - Objections	Awaiting Attention (Personal Identity)	Brain	Cerebrum
Computers	Consciousness	Dicephalus	Duplication	Fission
Human Animals	Human Beings	Modality	Note Links Explanation	Person
Plug Note Apologia	Replication	Self	Sleep	Thought Experiments
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

Aeon Papers - Summary Document: 2017-2018	Baker - Persons in the Material World	Brain	Brain Criterion	Brain Transplants
Cerebrum, 2	Clinical Observations, 2	Counting Persons	Fission, 2	Olson - Personal Identity - Oxford Bibliographies Online
Olson - What Are We? Animals, 2, 3	PID Note, Book & Paper Usage, 2, 3, 4, 5	Psychopathology	Thesis - Chapter 02 (What are We?), 2	Thesis - Chapter 03 (What is a Person?)
Thesis - Chapter 10 (Thought Experiments), 2, 3, 4, 5, 6, 7	Thesis - Chapter 12 (Conclusion)	Thesis - Current Stance	Thesis - Personal Identity, 2, 3, 4, 5, 6, 7, 8	Unity of the Person
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?
Baillie (James)	Commissurotomy and the Unity of Mind	Paper
Baillie (James)	Problems in Personal Identity	Book	2
Baker (Lynne Rudder)	Persons in the Material World	Paper		Yes
Barilan (Y. Michael)	One or Two: An Examination of the Recent Case of the Conjoined Twins from Malta	Paper
Bennett (M.R.) & Hacker (P.M.S.)	Methodological Reflections	Paper
Benson (Ophelia)	This Isn't My Body	Paper	2, 3	Yes
Berglund (Stefan)	Problems of Reductive Personalism	Paper
Braude (Stephen)	Multiple Personality and the Structure of the Self	Paper
Braude (Stephen)	The Principle of Compositional Reversibility	Paper
Briggs (Rachael) & Nolan (Daniel)	Utility Monsters for the Fission Age	Paper
Cerullo (Michael A.)	Uploading and Branching Identity	Paper	2
Davis (Lawrence H.)	Cerebral Hemispheres	Paper
Eccles (John)	Global Lesions of the Human Cerebrum	Paper	2
Eccles (John)	The Self and Its Brain	Paper
Gillett (Grant)	Brain Bisection and Personal Identity	Paper
Greenwood (John)	Split-Brains and Singular Personhood	Paper	2, 3, 4, 5
Hirsch (Eli)	Divided Minds	Paper
Liao (S. Matthew)	The Organism View Defended	Paper	2, 3, 4, 5	Yes
Lowe (E.J.)	On the Identity of Artifacts	Paper
Marks (Charles)	Commissurotomy, Consciousness and Unity of Mind	Book		Yes
Olson (Eric)	Personal Identity - Oxford Bibliographies Online	Paper		Yes
Olson (Eric)	What Are We? Animals	Paper	2, 3	Yes
Olson (Eric)	Why We Need Not Accept the Psychological Approach	Paper		Yes
Radden (Jennifer)	The Divided Minds of Mental Disorder	Paper
Reid (Mark D.)	A Case in Which Two Persons Exist in One Animal	Paper
Robinson (Daniel)	What Sort of Persons Are Hemispheres? Another Look at 'Split-Brain' Man	Paper
Robinson (John)	Personal Identity and Survival	Paper
Shoemaker (David)	Personal Identity and Immortality	Paper		Yes
Snowdon (Paul)	Animalism and the Unity of Consciousness	Paper
Sperry (Roger W.)	Hemisphere Deconnection and the Unity in Conscious Awareness	Paper	2
Sperry (Roger W.)	Some Effects of Disconnecting the Cerebral Hemispheres	Paper	2
Todman (Theo)	Thesis - Brain	Paper		Yes
Todman (Theo)	Thesis - Brain Criterion	Paper		Yes
Todman (Theo)	Thesis - Brain Transplants	Paper		Yes
Todman (Theo)	Thesis - Cerebrum	Paper	2	Yes
Todman (Theo)	Thesis - Chapter 02 (What Are We?)	Paper	2	Yes
Todman (Theo)	Thesis - Chapter 03 (What is a Person?)	Paper		Yes
Todman (Theo)	Thesis - Chapter 10 (Thought Experiments)	Paper	2, 3, 4, 5, 6, 7	Yes
Todman (Theo)	Thesis - Chapter 12 (Conclusion)	Paper		Yes
Todman (Theo)	Thesis - Clinical Observations	Paper	2	Yes
Todman (Theo)	Thesis - Counting Persons	Paper		Yes
Todman (Theo)	Thesis - Current Position	Paper		Yes
Todman (Theo)	Thesis - Fission	Paper	2	Yes
Todman (Theo)	Thesis - Personal Identity	Paper	2, 3, 4, 5, 6, 7, 8	Yes
Todman (Theo)	Thesis - Psychopathology	Paper		Yes
Todman (Theo)	Thesis - Unity of the Person	Paper		Yes
Van Inwagen (Peter)	Material Beings	Book
Van Inwagen (Peter)	Précis of Material Beings	Paper		Yes
Wilkes (Kathleen)	Being in Two Minds	Paper		Yes
Wilkes (Kathleen)	Consciousness and Commissurotomy	Paper
Wilkes (Kathleen)	Multiple Personality and Personal Identity	Paper
Wilkes (Kathleen)	Real People: Personal Identity Without Thought Experiments	Book		Yes

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References & Reading List

Author	Title	Medium	Source	Read?
Anderson (Robert M.) & Gonsalves (Joseph F.)	Sensory Suppression and the Unity of Consciousness	Paper - Cited	Behavioral and Brain Sciences, 4: 99-100, 1981	No
Aune (Bruce)	Changing Things	Paper - By Subtopic	Aune (Bruce) - Metaphysics: The Elements, Chapter 5	4%
Aune (Bruce)	Metaphysics: The Elements	Book - By Subtopic (via Paper By Subtopic)	Aune (Bruce) - Metaphysics: The Elements	4%
Baars (Bernard), Banks (William) & Newman (James)	Essential Sources in the Scientific Study of Consciousness	Book - By Subtopic (via Paper By Subtopic)	Baars (Bernard), Banks (William) & Newman (James) - Essential Sources in the Scientific Study of Consciousness	1%
Baillie (James)	Commissurotomy and the Unity of Mind	Paper - By Subtopic	Baillie (James) - Problems in Personal Identity, 1993, Chapter 7	No
Baillie (James)	Problems in Personal Identity	Book - By Subtopic (via Paper By Subtopic)	Baillie (James) - Problems in Personal Identity	45%
Baker (Lynne Rudder)	Persons and Bodies: A Constitution View	Book - Referencing (via Paper Referencing)	Bibliographical details to be supplied	Yes
Baker (Lynne Rudder)	Persons in the Material World	Paper - Referencing	Baker (Lynne) - Persons and Bodies, Chapter 1, pp. 3-88	Yes
Benson (Ophelia)	This Isn't My Body	Paper - Cited	From "Think" Website / The Philosopher's Magazine, 2005.	Yes
Benson (Ophelia)	This Isn't My Body	Paper - Referencing	From "Think" Website / The Philosopher's Magazine, 2005.	Yes
Blakemore (Colin) & Greenfield (Susan), Eds.	Mindwaves: Thoughts on Intelligence, Identity and Consciousness	Book - By Subtopic (via Paper By Subtopic)	Blakemore (Colin) & Greenfield (Susan), Eds. - Mindwaves: Thoughts on Intelligence, Identity and Consciousness	0%
Blatti (Stephan) & Snowdon (Paul), Eds.	Animalism: New Essays on Persons, Animals, and Identity	Book - By Subtopic (via Paper By Subtopic)	Blatti (Stephan) & Snowdon (Paul), Eds. - Animalism: New Essays on Persons, Animals, and Identity	22%
Bogen (James)	Further discussion on split-brains and hemispheric capabilities	Paper - By Subtopic	British Journal for the Philosophy of Science, Vol. 28, No. 3, Sep., 1977, pp. 281-286	No
Bogen (Joseph E.)	Mental Numerosity: Is One Head Better Than Two?	Paper - By Subtopic	Behavioral and Brain Sciences, 4: 100-101, 1981	No
Bradshaw (John L.)	In Two Minds	Paper - By Subtopic	Behavioral and Brain Sciences, 4: 101-102, 1981	No
Damasio (Antonio), Ed.	The 'Scientific American' Book of the Brain: The Best Writing on Consciousness	Book - By Subtopic (via Paper By Subtopic)	Damasio (Antonio), Ed. - The 'Scientific American' Book of the Brain: The Best Writing on Consciousness	2%
Davis (Lawrence H.)	Cerebral Hemispheres	Paper - By Subtopic	Philosophical Studies 87(2), August 1997: 207-222	No
Dewitt (Larry W.)	Consciousness, Mind, and Self: The Implications of the Split-Brain Studies	Paper - By Subtopic	The British Journal for the Philosophy of Science, Vol. 26, No. 1 (Mar., 1975), pp. 41-47	No
Eccles (John)	Mental Dualism and Commissurotomy	Paper - By Subtopic	Behavioral and Brain Sciences, 4: 105, 1981	No
Gazzaniga (Michael S.)	The Split Brain Revisited	Paper - By Subtopic	Damasio - The "Scientific American" Book of the Brain: The Best Writing on Consciousness	No
Gazzaniga (Michael S.)	The split-brain - Rooting consciousness in biology	Paper - By Subtopic	Proceedings of the National Academy of Sciences of the United States of America,Vol. 111, No. 51 (December 23, 2014), pp. 18093-18094	No
Geschwind (Norman)	The Perverseness of the Right Hemisphere	Paper - By Subtopic	Behavioral and Brain Sciences, 4: 106-107, 1981	No
Gillett (Grant)	Brain Bisection and Personal Identity	Paper - By Subtopic	Mind, New Series, Vol. 95, No. 378 (Apr., 1986), pp. 224-229	17%
Glover (Jonathan)	I: Philosophy and Psychology of Personal Identity	Book - By Subtopic (via Paper By Subtopic)	Glover (Jonathan) - I: Philosophy and Psychology of Personal Identity	6%
Glover (Jonathan)	Split Brains	Paper - By Subtopic	Glover - I: Philosophy and Psychology of Personal Identity, Chapter 2	No
Greenwood (John)	Split-Brains and Singular Personhood	Paper - By Subtopic	Southern Journal of Philosophy 31.3, 1993, 285-306	No
Gregory (Richard), Ed.	Oxford Companion to the Mind	Book - By Subtopic (via Paper By Subtopic)	Gregory (Richard), Ed. - Oxford Companion to the Mind	No
Hains (Brigid) & Hains (Paul)	Aeon: L-P	Book - Cited (via Paper Cited)	Bibliographical details to be supplied	33%
Hecker (Bruce)	How do Whales and Dolphins Sleep Without Drowning?	Paper - Cited	Scientific American, 2nd February 1998	Yes
Hershenov (David) & Taylor (Adam P.)	Split Brains: No Headache for the Soul Theorist	Paper - By Subtopic	Religious Studies: An International Journal for the Philosophy of Religion, 2014	5%
Hirsch (Eli)	Divided Minds	Paper - By Subtopic	Philosophical Review 100, 1991	No
Iredale (Mathew)	Your Two Brains	Paper - By Subtopic	TPM Online - February 2009	No
Joynt (Robert J.)	Are Two Heads Better Than One?	Paper - By Subtopic	Behavioral and Brain Sciences, 4: 108-109, 1981	No
Kinsbourne (Marcel)	Asymmetrical Function of the Brain	Book - Cited	Kinsbourne (Marcel) - Asymmetrical Function of the Brain	No
Kolak (Daniel) & Martin (Raymond), Eds.	Self and Identity: Contemporary Philosophical Issues	Book - By Subtopic (via Paper By Subtopic)	Kolak (Daniel) & Martin (Raymond), Eds. - Self and Identity: Contemporary Philosophical Issues	No
LeDoux (Joseph E.) & Gazzaniga (Michael S.)	The Brain and the Split Brain: A Duel With Duality As a Model of Mind	Paper - By Subtopic	Behavioral and Brain Sciences, 4: 109-111, 1981	No
Liao (S. Matthew)	The Organism View Defended	Paper - Referencing	The Monist, Vol. 89, No. 3, Coming into Being and Passing Away (July 2006), pp. 334-350	Yes
MacKay (Donald)	Divided Brains - Divided Minds	Paper - By Subtopic	Blakemore & Greenfield - Mindwaves	No
Marks (Charles)	Can a Single Mind Ever Have a Disunified Consciousness	Paper - By Subtopic	Marks - Commissurotomy, Consciousness and Unity of Mind, 1981, Chapter 6	Yes
Marks (Charles)	Commissurotomy, Consciousness and Unity of Mind	Book - Cited	Marks (Charles) - Commissurotomy, Consciousness and Unity of Mind	Yes
Marks (Charles)	Commissurotomy, Consciousness and Unity of Mind: Wittgensteinian Postscript	Paper - By Subtopic	Marks - Commissurotomy, Consciousness and Unity of Mind, 1981, Chapter 10	Yes
Marks (Charles)	How Does Disunity of Consciousness Bear upon Unity of Mind?	Paper - By Subtopic	Marks - Commissurotomy, Consciousness and Unity of Mind, 1981, Chapter 8	Yes
Marks (Charles)	How to Generate Philosophical Problems about Split-Brains	Paper - By Subtopic	Marks - Commissurotomy, Consciousness and Unity of Mind, 1981, Chapter 2	Yes
Marks (Charles)	In What Sense Do Split-Brain Patients Lack Unity of Consciousness	Paper - By Subtopic	Marks - Commissurotomy, Consciousness and Unity of Mind, 1981, Chapter 4	Yes
Marks (Charles)	Is the Consciousness of Split-Brain Patients Always Disunified?	Paper - By Subtopic	Marks - Commissurotomy, Consciousness and Unity of Mind, 1981, Chapter 5	Yes
Marks (Charles)	Mental Duality: An Unmade Case	Paper - By Subtopic	Behavioral and Brain Sciences, 4: 111-112, 1981	No
Marks (Charles)	Preliminary Analysis and Some Strategy	Paper - By Subtopic	Marks - Commissurotomy, Consciousness and Unity of Mind, 1981, Chapter 3	Yes
Marks (Charles)	Some Rough Truth Conditions for 'Split-Brain Patients Have One (Two) Mind(s)'	Paper - By Subtopic	Marks - Commissurotomy, Consciousness and Unity of Mind, 1981, Chapter 7	Yes
Marks (Charles)	The Split-Brain Syndrome: An Example of the Philosophically Puzzling Behavior Resulting from Commissurotomy	Paper - By Subtopic	Marks - Commissurotomy, Consciousness and Unity of Mind, 1981, Chapter 1	Yes
Marks (Charles)	Will an Adequate Psychology Favor a One-Mind Account of Split-Brain Patients?	Paper - By Subtopic	Marks - Commissurotomy, Consciousness and Unity of Mind, 1981, Chapter 9	Yes
Nagel (Thomas)	Brain Bisection and the Unity of Consciousness	Paper - By Subtopic	Nagel (Thomas) - Mortal Questions, 1979	Yes
Nagel (Thomas)	Mortal Questions	Book - By Subtopic (via Paper By Subtopic)	Nagel (Thomas) - Mortal Questions	Yes
Olson (Eric)	Papers on Identity Boxes: Vol 13 (Olson)	Book - Referencing (via Paper Referencing)	Bibliographical details to be supplied	16%
Olson (Eric)	Personal Identity - Oxford Bibliographies Online	Paper - Referencing	Oxford Bibliographies Online / Sheffield University website	Yes
Olson (Eric)	The Human Animal - Personal Identity Without Psychology	Book - Cited (via Paper Cited)	Bibliographical details to be supplied	Yes
Olson (Eric)	The Human Animal - Personal Identity Without Psychology	Book - Referencing (via Paper Referencing)	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 - Referencing	What Are We? A Study in Personal Ontology, Chapter 2 (November 2007: Oxford University Press.)	Yes
Olson (Eric)	Why We Need Not Accept the Psychological Approach	Paper - Cited	The Human Animal, September 1999, Chapter 3, pp. 42-72	Yes
Olson (Eric)	Why We Need Not Accept the Psychological Approach	Paper - Referencing	The Human Animal, September 1999, Chapter 3, pp. 42-72	Yes
Parkin (Alan)	Explorations in Cognitive Neuropsychology	Book - By Subtopic (via Paper By Subtopic)	Parkin (Alan) - Explorations in Cognitive Neuropsychology	Yes
Parkin (Alan)	The Split Brain	Paper - By Subtopic	Parkin - Explorations in Cognitive Neuropsychology, 1996, Chapter 6	Yes
Pinto (Yair)	When you split the brain, do you split the person?	Paper - Cited	Aeon, 26 September, 2017	Yes
Puccetti (Roland)	Brain Bisection and Personal Identity	Paper - By Subtopic	British Journal for the Philosophy of Science, 24:339-355 (1973)	No
Puccetti (Roland)	Mind with a Double Brain	Paper - By Subtopic	British Journal for the Philosophy of Science, Vol. 44, No. 4, Dec., 1993, pp. 675-691	No
Puccetti (Roland)	The Case For Mental Duality: Author's Responses + References	Paper - By Subtopic	Behavioral and Brain Sciences, 4: 116-123, 1981	No
Puccetti (Roland)	The Case For Mental Duality: Evidence From Split-Brain Data and Other Considerations	Paper - By Subtopic	Behavioral and Brain Sciences, 4: 93-99, 1981	No
Puccetti (Roland)	The Mute Self: A Reaction to Dewitt's Alternative Account of the Split-Brain Data	Paper - By Subtopic	British Journal for the Philosophy of Science, Vol. 27, No. 1, Mar., 1976, pp. 65-73	No
Puccetti (Roland)	Two Brains, Two Minds? Wigan's Theory of Mental Duality	Paper - By Subtopic	Kolak & Martin - Self and Identity: Contemporary Philosophical Issues	No
Reid (Mark D.)	A Case in Which Two Persons Exist in One Animal	Paper - By Subtopic	Blatti & Snowdon - Animalism: New Essays on Persons, Animals, and Identity, 2016: Part III, Chapter 12, pp. 253-265	42%
Rigterink (Roger J.)	Puccetti and Brain Bisection: An Attempt at Mental Division	Paper - By Subtopic	Canadian Journal of Philosophy, 10:429-452 (1980)	No
Robinson (Daniel)	What Sort of Persons Are Hemispheres? Another Look at 'Split-Brain' Man	Paper - By Subtopic	British Journal for the Philosophy of Science, Vol. 27, No. 1, Mar., 1976, pp. 73-78	17%
Rosen (Victoria)	One Brain. Two Minds? Many Questions	Paper - Cited	Journal of Undergraduate Neuroscience Education, 2018 Spring; 16(2): R48–R50	No
Schechter (Elizabeth)	Self-Consciousness and 'Split' Brains: The Minds’ I (TOC & Chapter 1: The Unity Puzzle)	Paper - By Subtopic	Retrieved from Academia.edu, 27/07/18	42%
Snowdon (Paul)	Animalism and the Unity of Consciousness	Paper - By Subtopic	Snowdon (Paul) - Persons, Animals, Ourselves - Chapter 8	7%
Snowdon (Paul)	Animalism and the Unity of Consciousness: Some Issues	Paper - By Subtopic	Blatti & Snowdon - Animalism: New Essays on Persons, Animals, and Identity, 2016: Part III, Chapter 13, pp. 266-282	33%
Snowdon (Paul)	Persons, Animals, Ourselves	Book - By Subtopic (via Paper By Subtopic)	Snowdon (Paul) - Persons, Animals, Ourselves	21%
Sperry (Roger W.)	Hemisphere Deconnection and the Unity in Conscious Awareness	Paper - By Subtopic	Baars, Banks & Newman - Essential Sources in the Scientific Study of Consciousness	11%
Thornton (Mark)	Double Brain, Double Person?	Paper - By Subtopic	British Journal for the Philosophy of Science, Vol. 45, No. 2, Jun., 1994, pp. 761-763	No
Todman (Theo)	Thesis - Commissurotomy	Paper - By Subtopic		Yes
Trevarthen (Colwyn)	Split Brain and the Mind	Paper - By Subtopic	Gregory - Oxford Companion to the Mind, pp. 740-6	No
Tye (Michael)	Can Anyone Else Feel My Pains?	Paper - By Subtopic	Tye - Ten Problems of Consciousness, 1995, Chapter 3	Yes
Tye (Michael)	Consciousness and Persons: Unity and Identity	Book - By Subtopic (via Paper By Subtopic)	Tye (Michael) - Consciousness and Persons: Unity and Identity	5%
Tye (Michael)	Split Brains	Paper - By Subtopic	Tye - Consciousness and Persons, 2003, Chapter 5, pp. 109-132	No
Tye (Michael)	Ten Problems of Consciousness	Book - By Subtopic (via Paper By Subtopic)	Tye (Michael) - Ten Problems of Consciousness	Yes
Van Inwagen (Peter)	Material Beings	Book - By Subtopic (via Paper By Subtopic)	Van Inwagen (Peter) - Material Beings	27%
Van Inwagen (Peter)	Two Problems About Personal Identity: Memory and Commissurotomy	Paper - By Subtopic	Van Inwagen - Material Beings; 1990; Ch. 16	Yes
Von Eckardt (Barbara)	Puccetti's Mental-Duality Thesis: A Case Of Bad Arguments	Paper - By Subtopic	Behavioral and Brain Sciences, 4: 113-114, 1981	No
Weinstein (Edwin A.)	Extinction and Hemi-Inattention: Their Relation to Commissurotomy	Paper - By Subtopic	Behavioral and Brain Sciences, 4: 114-115, 1981	No
Wilkes (Kathleen)	Being in Two Minds	Paper - By Subtopic	Wilkes - Real People: Personal Identity Without Thought Experiments, Chapter 5	Yes
Wilkes (Kathleen)	Consciousness and Commissurotomy	Paper - By Subtopic	Philosophy - 53, 1978, 185-97	No
Wilkes (Kathleen)	Real People: Personal Identity Without Thought Experiments	Book - By Subtopic (via Paper By Subtopic)	Wilkes (Kathleen) - Real People: Personal Identity Without Thought Experiments	Yes
Wilkes (Kathleen)	Unfused Homunculi	Paper - By Subtopic	Behavioral and Brain Sciences, 4: 115-116, 1981	No

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