The Self: my working model

Below is my current understanding and best explanation of the self. It's largely influenced by the ideas of David Deutsch (mainly our conversation and some podcasts/tweets) and Popper's chapter "Some Remarks on the Self" (Chapter P4 of The Self and Its Brain by Karl R. Popper and John C. Eccles). This is by no means a definitive or final viewpoint; it's intended to be updated and revised as I learn more.

• What Type of Thing Is the Self?
• What Does the Self Consist Of?
• What Is the Self's Aim?
• Is There One Self or Multiple?
• Why One Self Is the Default
• What Happens When There Are Multiple Selves?
• Is the Self Nature or Nurture?
• How Does the Self Develop?
• How Does the Self Persist Over Time?
• Future Additions

What Type of Thing Is the Self?

The Self is not a substance — neither a physical part of the brain nor an immaterial soul — but a process, or system of processes. Popper's insight is to describe the self and consciousness in terms of what they do, not some mysterious inner essence. In that sense, the self is an emergent but perfectly real phenomenon. By Deutsch's criterion, something is real when it plays an indispensable role in our best explanations, the ones that are hard to vary while still accounting for what they explain. Explanations, reasons, and selves all meet that standard, so they are as real as chairs or electrons, without being "ghost substances" or "an illusion".

More specifically, the self is a set of software programs instantiated in our universal and Turing-complete minds, which in turn are implemented in the physical substrate (hardware) of the brain.

What Does the Self Consist Of?

Our minds evolved via evolution and were not designed, so the description in terms of purpose-specific software programs is merely approximate, yet still accurate as a description of what they tend to do and how they work:

Broadly speaking, our mind has "firmware" which comes pre-installed from our genes, making it Turing-complete, and also gives us creativity (the ability to conjecture and criticize).

This firmware allows us to examine, improve, and create run-time generated software, which we can broadly divide into two categories:

• Content-level knowledge: internal knowledge about who we are and what we know. This includes things like: your plans for the week, your explanation of why a project failed, your sense that a melody is off-beat, your ability to ride a bike or kick a ball smoothly, your morning routine, your taste in design, your feeling that something in a deal is wrong, your hunger for food, your urge to pull your hand away from a hot surface, and your spike of tension before an important meeting.
• Process-level knowledge: Deutsch explains (via Popper's usage): an institution is a kind of idea, theory, habit, or practice that governs and facilitates how other ideas interact with each other in the mind. Creative institutions are ideas whose job is to manipulate other ideas and try to correct impediments to the growth of knowledge. They include modes of reasoning, modes of conjecture, modes of criticism.

Both content-level and process-level knowledge come in three types. Deutsch has broken this down into conscious explicit knowledge, conscious inexplicit knowledge, and unconscious knowledge (in my own terms: Statements, Intuitions, and Drives).

When is the Self there?

When we're in a "flow state" we're not aware of ourselves — we're fully immersed in the activity. This includes while we're creating knowledge and solving problems. The self seems to only become consciously present when there's a challenge within our mind that exceeds a certain threshold of difficulty. At that point, the self comes in to pursue its aim:

What Is the Self's Aim?

The self's aim is conflict resolution: it aspires towards unanimity between the parts of the mind which experience a problem. A problem is a conflict between two or more types of knowledge, and we can broadly distinguish the following problem-types:

Knowledge A	Knowledge B	The Problem type
I want it to be like this	But it's not like that	Undesired state
I expect this to happen	That actually happens	Disappointed expectation
This works like this	No, it works like that	Contradicting explanations
This theory explains A	But it doesn't explain B	Incomplete theory
I want A	But, I also want B	Conflicting goals

Conflict resolution happens via conjecture and criticism (creativity) across all three types of knowledge: explicit, inexplicit, and unconscious.

The self's aim is to resolve internal conflict and arrive at unanimity. It works through arbitration and conflict remediation, but we shouldn't think of the self as an arbiter above the process — more as a description of the process. The self isn't a judge sitting in a courtroom; it is the process by which the courtroom reaches a verdict. In a rational mind, this process converges on unanimity: a single self. In an irrational mind, it fragments.

Is There One Self or Multiple?

It's not absolutely one or the other; it can be both, because human minds are universal (Turing-complete) and can therefore construct any process- and content-level knowledge. However, one self is the normal and expected default.

Why One Self Is the Default

(Disclaimer: this is pure conjecture on my part.)

• Biologically, our genes are bound to one body, and for organizational purposes it makes sense to delegate in a somewhat hierarchical way: one primary arbiter or decision-maker with logical continuity. Without this, you constantly juggle between selves, lose memory chains, and risk acting irrationally. Rationality requires a persistent chain of memories and consistent use of values, which is also reinforced:
• Socially, it is functional to identify and label others as "one", which reinforces the same pattern. You use it to distinguish others, and they in turn distinguish you as one. It's useful to be coherent and consistent to others.

What Happens When There Are Multiple Selves?

(Disclaimer: this is pure conjecture on my part and doesn't go into clinical causes.)

• Repression: multiple voices may mean the primary arbiter and its unanimity-seeking behavior is being undermined, likely because some severe repression is occurring — a cry for help.
• Runaway simulation: we naturally compartmentalize internal selves with their own opinions to simulate what person X or person Y (mother, father, etc.) might think, or how our own identities ("the husband" vs. "the hard worker") would handle situations. When we take these simulations too seriously, irrational clashes can arise.
• Conflicting goals: it seems to be the case that when we experience the fourth problem type listed above (conflicting goals), we naturally spin up multiple selves to debate which goal we should pursue. The best fix is finding a common preference that all "selves" agree is important.

Is the Self Nature or Nurture?

There are certainly innate components and tendencies that we bootstrap our selves from, such as our tastes and desires, but these are merely a starting point. We actively create and construct our selves through how we interact with the world, and we can overwrite everything.

How Does the Self Develop?

We constantly conjecture and criticize new knowledge based on our interpretations and social interactions, integrating this consciously, inexplicitly, and unconsciously.

A newborn infant has sensations and experiences but lacks self-awareness. The baby feels hunger and pain but doesn't think "I am hungry" or "I am in pain." Self-consciousness, the ability to reflect on one's own mental states and recognize oneself as a distinct subject, develops gradually over the first years of life.

Key developmental milestones include:

• Body awareness (~6–12 months): learning to distinguish self from environment
• Mirror self-recognition (~18–24 months): recognizing oneself in a mirror
• First-person pronouns (~2–3 years): using "I" and "me" correctly
• Autobiographical memory (~3–5 years): forming coherent narratives about one's past

The development of the self inevitably results in individuation. Each person becomes unique through three compounding factors:

• Biological uniqueness: innate/genetic dispositions and capacities
• Experiential uniqueness: no two people encounter the same situations
• Self-shaping uniqueness: the choices and agency we exercise in constructing ourselves via the application of our creativity

How Does the Self Persist Over Time?

Not through an unchanging substrate, but through explicit conscious knowledge (in contrast to inexplicit or unconscious knowledge, what Popper seems to call "implicit" knowledge). It is important to note that these are always reconstructed, not reproduced, and are therefore fallible. Popper describes the following types of knowledge that anchor the self:

• Character and disposition: certain personality traits and dispositions persist: ways of thinking, values, and habits that create a coherent personality structure enduring despite gradual change.
• Projects and commitments: I am the same person because I continue the same projects, pursue the same goals, and maintain the same relationships. Identity is partly constituted by commitments and plans that extend through time.
• Memory chains:
  • Episodic memories (what happened): I remember who I was yesterday; that person remembers who they were the day before, and so on.
  • Semantic memories (what is): abstracted facts and understandings: this thing means that, I use this often, and so on.
• Social recognition: others recognize me as the same person, reinforcing my self-identity through their ongoing interactions with me.

Future Additions

The following are things I intend to add in the near future:

• The role of feelings/sensations/qualia as a feedback mechanism to signal the state of a current problem-solving process, or to alert to a new problem.
• A brief description of the functional role of consciousness.
• Whether a meaningful distinction can be drawn between the Self and non-self aspects of the mind.