David Marr

British neuroscientist (1945–1980) who recurs in the vault along two distinct threads. His three levels of analysis — computational, algorithmic, implementational — are a standing framework the vault reaches for when separating what a system computes from how it is wired, appearing across the substrate-laundering and rational-analysis notes. Separately, his 1969 theory of the cerebellar cortex (extended by Ito 1970 and Albus 1971) is the seed of one of the vault's cases of a computational circuit theory whose synaptic rule was confirmed experimentally only later — though the rule that was confirmed, parallel-fiber–Purkinje-cell long-term depression, was Ito's 1970 revision, not Marr's: Marr's own model assumed synaptic potentiation, and the sign flip is a defining difference between the two. The confirmation came from Ito's own lab in 1982.

References

• claim-marr-ito-cerebellar-ltd-1969-confirmed-ito-kano-1982 — the 1969/70 cerebellar LTD theory, confirmed 1982
• observation-substrate-laundering-across-marr-levels — Marr's levels as a lens on substrate independence
• claim-rational-analysis-anderson-optimal-solution-marr-level — rational analysis at Marr's computational level
• claim-anderson-traces-rational-analysis-lineage-to-brunswik-gibson-marr-shepard — Anderson's own ancestry claim, with Marr as one of two "more recent" figures giving rigorous form to an older Brunswik/Gibson adaptationist tradition
• Pattern context: claim-neural-circuit-theories-wait-decades-for-anatomical-confirmation

Log

• 2026-08-28: Anderson's 1991 BBS précis names Marr (with Shepard) as providing "rigorous developments" of a perception-adaptationist tradition traced back through Brunswik and Gibson — a positioning of Marr the vault hadn't recorded before, distinct from the three-levels and cerebellar-theory material above (claim-anderson-traces-rational-analysis-lineage-to-brunswik-gibson-marr-shepard).
• 2026-09-13 (propagation-repair): cerebellar-theory paragraph corrected. Was: Marr's 1969 theory described as the case "whose synaptic rule — parallel-fiber–Purkinje-cell long-term depression — was confirmed experimentally only later," attributing the LTD rule to Marr. Now: the LTD rule is Ito's (1970) alone; Marr's 1969 model assumed synaptic potentiation, and the 2020 Kawato/Ohmae/Hoang/Sanger review names "potentiation versus depression of synaptic plasticity" as a defining difference between the models. Propagates the AUDIT 2026-07-19 correction to claim-marr-ito-cerebellar-ltd-1969-confirmed-ito-kano-1982. Unchanged: the 1969/1970/1971 Marr–Ito–Albus lineage, Marr's priority as the model the others extend, and the 1982 same-lab confirmation.