>[!abstract] >My own proposal for a continuum of whether knowledge is had and achievable. In this framework, I propose three nested domains of knowledge: **personal** (held in memory, and subject to learning reinforcement and forgetting), **societal** (distributed memory in our collective brains, archival records, and archeological artefacts), and **metaphysical** (discoverable and non-discoverable unknowns), with a correspondence between them at the subdomain level. The radius of knowability tells us whether the knowledge is achievable, and under which conditions. ## A. The personal domain The personal domain pertains to the individual knowledge held in a given person’s memory. ===That knowledge may reside either proximally in their memory, or distally in some personal knowledge management system (PKMS), such as a [[Zettelkasten]]. In the latter case, the person must have possessed that knowledge at some point in the past, and simply chose to offload it to a PKMS until the next recall. Otherwise, the case would be indistinguishable from that in which the person never had the knowledge in the first place, and would simply go on about procuring it as and when needed (e.g., by prompting an LLM or search engine). The nuance here is tenuous but important. Given that virtually all human knowledge on record can be accessed online at an ever-decreasing latency and marginal cost, the only boundary that can effectively define the personal domain of knowledge is whether the person currently has that knowledge, or had it in the past and uses a tool to facilitate recall. Knowledge that was never in a person’s memory does not qualify as personal knowledge, even if the person can trivially discover it. There is, of course, a restrictive case to be made for the personal domain to be defined by only the knowledge that a person currently possesses. However, because [[Forgetting curve|forgetting follows a curve]], recall may range from spontaneous to assisted (e.g., memory jogging, cues, hypnosis) to impossible. This leads to the following proposed classification.=== ### A1. Personal knowledge that is known and can be expressed This is knowledge that a person readily possesses **and** can articulate to others (even if with varying degrees of accuracy, confidence and conscious effort). At the heart of this subdomain are straightforward facts, such as knowing that tomatoes are fruits, or that gravity results from the curvature of spacetime. Also included in this subdomain, but further away from its central core, is knowledge which has been sufficiently, but not completely, forgotten that some assisted recall is required. That assistance may include memory jogging, hypnosis, or the use of a personal knowledge management system (PKMS) where notes are kept. An example might be the PIN code for an old expired credit card, or how to do divisions by hand. At the outer limits of this subdomain is knowledge that is derived from muscle memory, yet can still be expressed with some deliberate effort. For example, if I rely on muscle memory alone to enter my computer password every day, I may need to consciously pay attention while typing it once more before I am able to spell it out for someone else. Likewise, I know how to tie a tie, but might need to go through the physical motions in order to provide stepwise instructions to someone else. ### A2. Personal knowledge that is known but cannot be expressed This is tacit knowledge that a person can prove to be in possession of, but is unable to express. An example might be the muscle memory of playing a musical instrument, or intuitively knowing the best move in a game of chess thanks to decades of training from an early age. A person cannot convey that knowledge to another, short of training that other person over an arbitrarily long time period (and even then, there is a hard limit: no adult who is a novice at chess can expect to become as proficient as Magnus Carlsen, even if coached by Magnus himself for the rest of their lives). Conversely, I can be described how a musical instrument or the game of chess are played, and yet be no more meaningfully competent at either from having that knowledge. For all practical purposes, that type of knowledge is locked inside a person’s head. ### A3. Personal knowledge that is not known, and thus cannot be expressed Centrally, this is truly forgotten knowledge that cannot be recalled under any circumstance; the information has dissipated from a person’s brain and is beyond even assisted retrieval. An example might be memories formed at a very early age, or the name of someone who introduced themselves to you in passing at an event many years ago. Peripherally, this subdomain also includes knowledge that never entered the person’s consciousness. This is equivalent of the irrational numbers on the number line: there are infinitely more of those that there are rational numbers. The knowledge that we never personally possessed is vastly larger than the one we do or ever did, and in fact may well be unbounded. This subdomain is also a natural segue into the next. ## B. The societal domain ### B1. Societal knowledge that is known and can be conveyed to me This subdomain contains all of present day humanity’s knowledge that I can learn from others (including, passively, from documental records such as textbooks). The archetypal example is the curriculum of a school; pupils start their educational journey devoid of it, and leave school many years later in possession of that knowledge. Also included here is knowledge that is not in any person’s individual memory, but is still readily accessible from our collective documental record, such that it can be retrieved trivially and is not considered lost. For example, some historical account of what happened on a particular date and city, as found in newspaper archives. ### B2. - Pertains to the collective knowledge held by humanity. - Collective knowledge is the sum of all living individuals' knowledge (including overlaps and contradictions, where two or more individuals may disagree on a certain knowledge), and of the readily accessible record ([[Documentality|documents]]). | Circle | Description | | ---------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ | | A1. Stuff I know and can articulate | This is classical knowledge: I can instruct others about that knowledge, with varying degrees of accuracy and confidence depending on how comfortable I am with the materials. The [[Feynman technique]] can help me reinforce my own understanding so I can explain it better. | | A1b. Stuff I don't know, have known at some point, and could remember under specific circumstances. This is just a variant of A1 | This is quasi-[[Forgetting curve\|forgotten]] knowledge, such as an old credit card PIN code, or fluency in a language that I learned at school but never practiced since, etc. It might come back to me with some memory jogging, recall practice, hypnosis, etc. | | A2. Stuff I know but cannot articulate | This matches [[Polanyi’s paradox]]: there is tacit knowledge that I can prove I know, but which I cannot articulate. This includes muscle memory, like typing a password and yet struggling to spell out that password to someone else, or riding a bike. Or, some non-physical memory that forms part of the general know-how and resists codification. | | A3. Stuff I don't know, have known at some point, but will never remember | This is truly [[Forgetting curve\|forgotten]] knowledge, i.e., knowledge that I would not be able to recall under any circumstance; the information has dissipated from my brain and there is no retrieving it even if presented with a multiple-choice question about it that contains the correct answer. For example, the name of someone I briefly met at a conference many years ago. | | B1. Stuff I don't know, but others do and can tell me | This is human knowledge that I don't possess but could learn from others (or possibly discover by myself). | | B1b. Stuff I don't know, no one else knows either, but was known at some point and could be retrieved under specific circumstances. This is just a variant of B1 | This is stuff that was once part of humanity's knowledge, even if just one person's; that knowledge is gone from people's memories, but it could be retrieved under specific circumstances: archeological dig, search in the historical records, reading unique ancient books, etc. | | B2. Stuff I don't know, but others do and yet cannot tell me | This is stuff I don't know, and which forms part of other people's tacit knowledge; it resists codification by them so I cannot easily gain that knowledge from them (for example, Magnus Carlsen cannot fully transfer his chess-playing abilities to me, even if we spend the rest of our lives training together). | | B3. Stuff I don't know, no one else knows either, was known at some point but is now gone forever | This is stuff that was once part of humanity's knowledge, even if just one person's; but that knowledge is gone and irretrievable. For example, whether Emperor Montezuma had any moles on his face. | | C1. Stuff I don't know, no one else knows either, but is discoverable | This is beyond humanity's current knowledge, but presumed to be within reach. For example, the weather at the same time next year (we cannot predict it but we will eventually find out); or the proof to some mathematical conjecture. This is the equivalent to Rumsfeld's "[[Unknown unknowns]]". | | C2. Stuff I don't know, no one else knows either, and the universe won't tell us (it exists but is physically undiscoverable) | This is beyond humanity's capacity to know, for example whatever is inside a black hole, or beyond the visible universe (outside of our [[Light cone\|light cone]]). We can only speculate about what is beyond the limits of knowledge ([[De Docta Ignorantia]]). | | C3. Stuff that was never attainable knowledge in the first place | This is the domain of [[Mu]], such as "do we have free will?". | >[!related] >- **North** (upstream): [[Epistemology]] >- **West** (similar): — >- **East** (different): — >- **South** (downstream): —