Personal identity — the conscious awareness of self — originates in the cleavage of a nebulous universe into “self” and “world”. As the brain develops and diverse capabilities emerge, many of which are entwined with “self”, personal identity becomes more complex. Its functions and features transform. John Locke made an initial contribution, the notion that personal identity depends on a continuous autobiographical memory. The list below starts with autobiographical memory, and adds five additional components.

Components of Personal Identity

• Autobiographical identity “I was born; I will live on a linear trajectory through space and time; I remember many of the events along that timeline. I will die sometime in the future” This is essentially Locke’s contribution.I am the person who lived the narrative of my life. (Locke on personal identity).

• Body identity “My body is the boundary of my self. I am what is within my skin. I have a ‘feeling’ of my body, that is me. My body has been with me all of my life, and is the center of where I am.”  The body houses the conscious self. (The “Personal Identity” entry in the Stanford Encyclopedia of Philosophy, refers to this as thee “somatic approach“)

• Sense of Agency “I can change the world in certain ways, not in others.” Agency involves both physical abilities and social abilities. Physically, it involves the ever-evolving sense of what your body can and cannot do: “Can I lift that large box?”. Social agency involves a person’s role in group action: “Can I persuade my friends to join me in this project?”. Agency is at the center of self-world interactions. (Links: My post: Personal Identity and agency, Pretty good wikipedia summary Sense of Agency. Also see, Marya Schectman, The Constitution of Selves)

• Social identity “I am member of several groups. Sometimes I feel no boundary between myself and a particular group; group successes and failures are my own successes and failures.” Groups include family, community, ethnic gout, sports team, work institution, religious affiliation, country, all humans, all sentient beings. Social identity also involves networks of interaction — friends, acquaintances, teachers, classmates, bosses, employees. These social networks produce social roles. As a teacher, I behave differently than as a father, friend or husband. (Wikipedia entry on social identity seems OK.)

• Beliefs “I believe that the earth is round, that the sun rose yesterday, that it will rise tomorrow, and that my friends are true friends. I am a liberal, and believe in human potential and human progress. I believe I am not a brain in a vat.” I use “belief” as a Bayesian term, but I think it corresponds with common usage. In this line of thinking, there are no “facts” only beliefs with different probabilities of certainty. I might say “I believe the Affordable Care Act will work” and “I believe know that gravity is the force that keeps me grounded”. While I might say “I know” for some statements, treating them as facts (as one might say, “I know that gravity keeps me grounded”), they are really strong beliefs.

  Continuing this line of thinking the “knowledge” that we hold in our brains is a single complex Bayesian structure, with many interacting components. In an earlier post, I described this composite structure, metaphorically, as a geodesic (wishful and rational beliefs). For example, I tend to believe the statements of prominent physicists. If, for some reason, I came to believe that physics was a cult, and physicists were liars and fools, many of my beliefs about the nature of the world would be undermined. Such fundamental changes rarely occur. My belief structure is largely stable. While this structure changes daily, it changes slowly. Yet, over time, the evolution of this belief structure can change dramatically, and still be part of my identity. I can, roughly, explore my autobiography and recall past belief states, recognizing them as part of my identity, yet different from my current belief structure. For example, I can remember when I believed that Santa Claus was real and that God had a white beard (I had a picture bible). This is a large topic that needs further exploration. For the present I’ll assert that a coherent, unified belief structure is a component of personal identity.

• Conscious identity “I am the author of my subjective experience.” This can be called “conscious agency”, the internal ability to direct stream of consciousness. This borders on “free will” and interacts with all other critical features. This is here for two reasons. First, to reinforce the role of consciousness in identity (although it may be implicit in the other features). Second, because the sense of authorship and mental agency is important. Note that this is not covered by “agency”, above, because of the felt ability to create imagined scenes, actions and concepts.

Comments.

First, the list is tentative and speculative. I invite comments and critique.

Second, the “components” may not be independent. There are clear interactions. For example, consciousness is involved in almost all. The boundary conditions may not be crisp or ideal.

Third, feature descriptions are uneven. The longest is “beliefs”. Self-evident features have short descriptions.

Fourth, several items on the list are unconventional, most notably the last two (‘beliefs’ and ‘conscious identity’.

Fifth, I apologize for leaving out references. I am aware that others discuss the first three components. I am not aware of discussion of the final two. (March 30; added some links)

Finally, I haven’t presented empirical support for these assertions. Some is available from neurology, psychiatry, psychology and neuroscience. Neurological syndromes where some features may be lacking are good points of entry. These may include

• amnesia — autobiographical memory
• locked-in syndrome — agency
• schizophrenia — beliefs
• sociopathy — group agency
• body neglect — body identity
• amputation — body identity
• prosthesis (and tool) use — agency and body identity
• denying ownership of part of body (asomatognosia) — body identity

Update March 30. More comments:

Following Locke, a core features of object identity are singularity and continuity. This general concept applies to personal identity. Although I have not applied this criterion in the list, above, it holds up fairly well. Certainly applies to the classic components of personal identity, consciousness (autobiography) and body.

Personal identity can be approached from a first person or a third person  perspective — “I can throw a ball” vs “he can throw a ball”. First person seems primary, second person is frequently inferred, frequently via language. I think the following works: If one constructs a sentence beginning with “I”, you will be able to assign it one of the categories above. (Same with “he” or “she”). Each item on the list is followed by a first person narrative example beginning with “I”.

My guess is that some will feel that combining #1 and #2 (conscious and body continuity) with items like “social identity” is a categorical mistake: these are different things, apples and oranges that happen to go by the same name. If so, I’d like clarity on the issue.

Another issue is the relation of property to personal identity. Are you what you own? What counts as “property”? Its pretty clear that your car or house may be your property, but is not you. But there may be borderline cases. What about the information in your DNA code?

Can personal identity, or features of components of PI, be information? In the list above, it can be argued that a set of beliefs could be coded as information. A fingerprint is information. The DNA code is certainly information. Could these be part PI? Are they personal property?

Another topic is body image and appearance. These are certainly part of the sense of self. In what respects are they PI? Could they be property? My first inclination is to call your DNA code property. You did not create it, you inherited it. Appearance and body image are more difficult. Perhaps they fall under list item 2, Body Identity.

Please comment and/or discuss.