---
slug: foundationalism
name: Foundationalism
one_liner: "Halt a chain of same-kind dependencies at basic elements that are grounded in a different way and require no further support — the terminating dual of infinite regress along the does-the-chain-end axis."
type: prime
schema_version: 2
status: density_v2_draft
categories: [epistemic, structural]
origin_domain: epistemology
alternate_origin_domains: [mathematics_logic, philosophy_metaphysics, computer_science]
aliases: [foundationalist_structure, basic_beliefs, grounded_termination, axiomatic_grounding, regress_stopper]
related: []
solution_archetypes: []
review_flags:
- "OPERATOR-DERIVED (op-01 dualization, sub-flavors 1a/1c) — the structural dual of `infinite_regress` along the does-the-chain-terminate axis: it is the regress-STOPPER that ends the same-kind dependency chain in a different-kind foundation. Discovered in the op-01 full sweep 2026-07-03; 3 independent routes proposed it (1a, 1c, re-pilot). Verified absent via search_prime + slug check. STATUS: HOLD — pending owner curation."
- "Created 2026-07-03; STUB ONLY (frontmatter + Core Idea + Notes). Did NOT go through Phase-A triage. SI/SF/similarity grades are PROPOSER ESTIMATES pending triangulation. Body sections (Structural Signature onward) NOT yet written."
- "Phase-C action: re-similarity check vs infinite_regress / coherentism (the third regress-exit) / axiom / grounding / recursion base-case to confirm it does not collapse; decide whether the right object is the foundationalist EXIT specifically or a broader 'regress-termination / base-case' prime of which foundationalism and mathematical recursion base-cases are instances. Draw the sibling edge to `infinite_regress` and any co-sibling edge to a coherentism prime at incorporation. one_liner must be synced to a v1 draft per CLAUDE.md before merge."
substrate_independence:
  composite_substrate_independence: 4
  domain_breadth: 4
  structural_abstraction: 4
  transfer_evidence: 3
  reasoning: 'The core structure — terminate a chain of same-kind dependency relations at basic elements that are grounded in a different way and need no further support — is a topological property of a dependency graph (a set of ungrounded-elsewhere roots that halt the regress), medium-neutral in principle, so structural abstraction is a strong 4 (it is slightly below a pure 5 because the "different structural kind" of the foundation is what does the work, and that kind is often specified in domain terms). It recurs beyond epistemology: axioms terminating chains of proof in logic and mathematics, base cases terminating recursion in computer science, fundamental/ungrounded entities terminating chains of metaphysical grounding, and self-evident/basic beliefs terminating chains of justification in epistemology — a domain breadth of 4. Transfer is real and recognized (the axiom-as-regress-stopper and the recursion base-case are transparently the same move as the foundationalist basic belief) but the concept is most sharply developed in its philosophical home, so transfer evidence is 3 and the composite is 4.'
similarity_to_nearest_existing_prime:
  slug: infinite_regress
  similarity: 0.7
structural_framed:
  label: mixed-structural
  aggregate: 0.34
  criteria: {vocab_travels: 0.3, evaluative_weight: 0.2, institutional_origin: 0.3, human_practice_bound: 0.2, import_vs_recognize: 0.5}
  rationale: 'The underlying structure — a dependency chain halted at different-kind, self-supporting roots — is a graph-termination property and reads structural. But "foundationalism" is a named -ism from a specific philosophical debate (institutional_origin 0.3), it carries the doctrinal vocabulary of that debate that must partly travel (vocab_travels 0.3), and the label is substantially a term of art one imports rather than a structure one bare-recognizes (import_vs_recognize 0.5). Those pull the aggregate to 0.34: predominantly structural in mechanism but framed by its epistemology-doctrine packaging — which is exactly the hold-worthy tension (is the prime the structure, or the doctrine?).'
phase_b_passes_completed: []
---
# Foundationalism

## Core Idea

Foundationalism is the structural move of *stopping a regress by grounding it in elements of a different kind*: given a chain of same-kind dependency relations — each belief justified by a further belief, each truth grounded in a further truth, each element depending on another of its own type — foundationalism terminates the chain at a set of *basic* elements that are not supported in the same way as the rest and require no further support of that kind. It is one pole of a single structural axis — *does the same-kind dependency chain terminate, and if so, how?* — whose opposite pole is `infinite_regress` (the chain iterates without natural end). Where the input prime names the non-terminating structure, foundationalism names the terminating one, and it is one of exactly two ways a regress can be halted: end it at a *different-kind* foundation (foundationalism) or loop it back on itself (coherentism/circularity). The load-bearing feature is that the terminator is of a *different structural kind* from the links it terminates — basic beliefs are not justified-by-another-belief, axioms are not proved-from-another-theorem, base cases are not defined-in-terms-of-a-smaller-case — so the regress is broken not by continuing the chain but by *changing the kind of support* at the bottom.

The defining commitments are three. First, there is a *same-kind dependency chain*: a relation ("is justified by," "is grounded in," "is defined in terms of") that, applied to any element, produces another element of the same type asking the same question — this is precisely the structure that, left alone, produces the regress. Second, there is a *distinguished basic set*: elements that terminate the chain because they stand in a *different* support relation (self-evidence, direct acquaintance, stipulation, brute fact) or none at all — they are where the "why?" is answered by something other than another link. Third, there is *directed grounding upward*: every non-basic element traces, through finitely many same-kind steps, back to the basic set, so nothing floats unsupported. The characteristic payoff is *termination without circularity*: the chain ends, so the whole edifice is finitely grounded and non-basic elements inherit their standing from the base. The characteristic cost — the reason this is a genuine choice and not a free lunch — is that it *relocates the burden onto the foundation*: the basic elements themselves cannot be supported in the ordinary way (that is what makes them basic), so the account is only as secure as its claim that those elements are legitimately self-standing. The regress is not dissolved but *paid off in a different currency*, and the whole dispute over a foundationalist account is a dispute over whether that currency is good.

Read as different-kind termination of a same-kind chain, the pattern recurs well beyond its epistemological home. In **logic and mathematics** it is the *axiom*: a chain of proof, each theorem derived from prior theorems, terminates in axioms that are *stipulated* rather than proved — the regress-stopper of a different kind. In **computer science** it is the *base case* of a recursive definition: each call reduces to a smaller call of the same kind until a case that is answered *directly*, not by further recursion, halts the descent — an unterminated recursion is exactly the computational face of infinite regress. In **metaphysics** it is *fundamentality*: chains of grounding (the mental grounded in the physical, the physical in the microphysical…) terminate in fundamental entities that are ungrounded-in-anything-further. Across all of these the recognizable move is the same — do not continue the chain and do not loop it; end it at elements whose support is of a different structural kind, and accept that the security of the whole now rests on the legitimacy of that foundation.

## Notes

**Provenance.** Produced by the op-01 dualization operator (sub-flavors 1a and 1c) as the structural dual of `infinite_regress` along the *does-the-chain-terminate* axis — foundationalism is the regress-stopper that ends the same-kind dependency chain in a different-kind foundation. Strong convergence signal: **three independent routes** proposed it in the sweep (1a, 1c, and the re-pilot). Verified absent via search_prime + slug check. Manifest verdict: STRONG (but filed HOLD pending owner curation).

**For owner evaluation (keep/cut).** The case FOR: this is a co-equal structural dual of an existing prime, it names an *established* structure in epistemology (and its axiom / base-case / fundamentality cognates are transparently the same move across logic, CS, and metaphysics), it has strong three-route convergence, and it fills a real slot — the input prime `infinite_regress` explicitly names foundationalism as regress-exit (a) but the corpus has no prime for it. The specific risks Kurt should weigh, which are why this is a HOLD and not an auto-accept: (1) **structure-versus-doctrine framing risk** — "foundationalism" is a named philosophical *-ism* carrying doctrinal baggage (SF aggregate est. 0.34, the highest of this batch). The genuinely prime-worthy object is the *structural* move (halt a same-kind chain at a different-kind base), and the question is whether to name the prime after the doctrine or after the structure — a more neutral slug such as `grounded_termination` or `regress_termination` might carry the structure without the doctrinal frame. (2) **granularity / genus risk** — foundationalism is *one of two* regress-exits (the other being coherentism/circularity, which the corpus may also lack); the better hold could be a single parent prime "regress termination" of which foundationalism (different-kind exit) and coherentism (loop-back exit) are the two children, with mathematical recursion base-cases as instances of the foundationalist branch. Kurt should decide the level: name the specific exit, or name the axis of exits. (3) **collapse-into-input risk** — similarity to `infinite_regress` is high (est. 0.7) because the two are defined against each other; confirm foundationalism carries enough independent content (the different-kind foundation, the burden-relocation trade) to stand as its own prime rather than as a subsection of the regress prime. There is a clear **pair-completion / lattice-gap signal** here: infinite_regress + foundationalism (+ possibly coherentism) want to sit together under a regress-structure parent.

**At incorporation.** Re-similarity-check against `infinite_regress` (collapse test), any `coherentism` / circularity prime (the co-sibling regress-exit), `axiom`, `grounding` / `fundamentality`, and the recursion base-case to fix the right granularity. Decide the naming question (doctrine-slug `foundationalism` vs structure-slug such as `grounded_termination`) before densifying, since it changes the SF character and the Core Idea's register. Draw the sibling edge to `infinite_regress` and, if a coherentism prime is created or exists, the co-sibling edge; consider proposing the shared parent (regress-termination) to close the lattice gap. Sync the `one_liner` to a v1 draft per CLAUDE.md before merge, mirrored across v1/v2 in the same commit.
