AIM Framework glossary
Heuristic
Canonical definition
A Heuristic is a class of Object, Individual or event that the Thinker holds as a prior, together with the rule that answers a question about a case by the class the case is assigned to, so that a continuous and largely unobserved world is modelled in terms a serial Ground-Resolution can compute with. Heuristics are how an Individual makes a workable model of the world, and the term carries its sense in the psychology of judgement: an economical procedure that substitutes a question the Individual can answer for one the Individual cannot, usually effective and in error systematically and predictably. A Heuristic is maintained by the Thinker and revised only by Bayesian Updating, and a Heuristic acts faster than deliberation, because the Heuristic's classes are among the templates the Observer reads from the Belief Register and under which the Observer classifies the field into Objects. Every Heuristic is coarser than the Referent the Heuristic models. Most Heuristics are acquired and maintained on testimony, so Contactless Updating moves them, and each Heuristic sorts the Evidence that would test the Heuristic, so a Heuristic departs from its Referent unless the Individual holds the Referent prior to the Heuristic and not subordinate to the Heuristic. Held subordinate to the Referent, a Heuristic is a workable model; held prior to the Referent, the Heuristic becomes a claim that its classes are the world's own divisions, which an available decohered Referent defeats.
Explanation
No one can think about every case from scratch, so the mind sorts the world into kinds and answers questions about a case by asking what kind it is. That sorting is a heuristic, and it is how anyone builds a working picture of the world at all. It is usually good enough and wrong in predictable ways, because a kind leaves out what makes its members different. The danger is not in having heuristics, which no one can avoid, but in forgetting that they are maps. Most of the kinds a person uses were learned from other people, and they shift with what other people say rather than with how the world is; they also decide how new evidence gets sorted, so they tend to confirm themselves. The protection is to keep the world in charge: to treat a kind as a guess about how things divide, and to change it when the world says otherwise. The races and genders a culture recognises at any time are heuristics of this kind. Using them is unavoidable; treating them as nature's own divisions, or as ranks, is what the evidence about human variation rules out.
Epistemic status
Inherited (the heuristics-and-biases literature) with Framework-Specific Extensions.
Derivation
Also in the entry
Distinction from Habit. A Habit is selection on the Decision Hub's cached-value store, which holds a value and no class and which the Thinker does not write. A Heuristic is a class the Thinker holds and the Observer applies. Both run faster than deliberation, by different routes.