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Title page identifies the 1957 second impression of the 1956 book. Use section numbers as the stable locator: the electronic PDF places two printed pages on each PDF page. Rights statement permits educational and research distribution with its notice; this packet links and paraphrases.", "creators": [ "W. Ross Ashby" ], "doi": "", "isbn": "", "publisher": "Chapman & Hall", "licence": "archive_access_check_reuse", "archived_url": "https://www.ashby.info/", "content_hash": "", "review_status": "passage_checked_research_pass", "last_checked": "2026-10-29", "public_link_status": "public_link", "connection_pass": "depth_20261029", "source_locator": "1957 second impression; sections 11/5–11/11, printed pp. 205–209; PDF pp. 109–111", "access_note": "Use section numbers as the stable locator: the electronic PDF places two printed pages on each PDF page. Rights statement permits educational and research distribution with its notice; this packet links and paraphrases." }, { "id": "src_ashby_archive_biography", "title": "Biography: W. Ross Ashby (1903–1972)", "source_type": "family_archive_history", "quality_tier": "B", "access": "public", "url": "https://ashby.info/biography.html", "date": "2008-01-01", "notes": "Biography by Ashby's daughter Jill, using Ashby's autobiographical notebook, family research and memories. It dates development of requisite variety to 1952–1953 and the writing of An Introduction to Cybernetics to 1952–1956.", "creators": [ "Jill Ashby" ], "doi": "", "isbn": "", "publisher": "W. Ross Ashby Digital Archive", "licence": "site_terms", "archived_url": "", "content_hash": "", "review_status": "research_pass_needs_editor", "last_checked": "2026-08-09", "public_link_status": "public_link" }, { "id": "src_conant_ashby_good_regulator_1970", "title": "Every Good Regulator of a System Must Be a Model of That System", "source_type": "primary_text", "quality_tier": "A", "access": "public", "url": "https://doi.org/10.1080/00207727008920220", "date": "1970", "notes": "Primary article text opened and inspected at Principia Cybernetica. Electronic transcription contains formatting errors in some equations. Locators here identify its PDF pages, not invented original journal page correspondence.", "creators": [ "Roger C. Conant", "W. Ross Ashby" ], "doi": "10.1080/00207727008920220", "isbn": "", "publisher": "International Journal of Systems Science 1(2), 89–97", "licence": "publisher_terms", "archived_url": "", "content_hash": "", "review_status": "passage_checked_research_pass", "last_checked": "2026-10-29", "public_link_status": "public_link", "reading_url": "https://pespmc1.vub.ac.be/books/Conant_Ashby.pdf", "connection_pass": "depth_20261029", "source_locator": "Theorem, proof, and subsequent comments, electronic PDF pp. 8–9; section 5, Discussion", "access_note": "Electronic transcription contains formatting errors in some equations. Locators here identify its PDF pages, not invented original journal page correspondence." }, { "id": "src_metaphorum_vsm_2026", "title": "Viable System Model - The VSM in 1000 words", "source_type": "professional_community_explainer", "quality_tier": "C", "access": "public", "url": "https://metaphorum.org/staffords-work/viable-system-model", "date": "2026-08-09", "notes": "Metaphorum explainer identifying Ashby's requisite variety, Wiener's cybernetics and the mathematics of recursive systems among the VSM's theoretical bases. Used as a public bridge source pending exact primary-book locators.", "creators": [ "Metaphorum" ], "doi": "", "isbn": "", "publisher": "Metaphorum", "licence": "site_terms", "archived_url": "", "content_hash": "", "review_status": "research_pass_needs_editor", "last_checked": "2026-08-09", "public_link_status": "public_link" }, { "id": "src_scio_requisite_inefficiency_2014", "title": "Requisite inefficiency", "source_type": "official_professional_body_talk_page", "quality_tier": "B", "access": "public", "url": "https://www.systemspractice.org/resources/requisite-inefficiency", "date": "2014-09", "notes": "SCiO record of Ivo Velitchkov's proposal that some apparent inefficiency preserves excess variety needed for longer-term viability.", "creators": [ "Ivo Velitchkov" ], "doi": "", "isbn": "", "publisher": "SCiO", "licence": "site_terms", "archived_url": "", "content_hash": "", "review_status": "checked", "last_checked": "2026-08-10", "public_link_status": "public_link" }, { "id": "src_taylor_clarity_practices_2024", "title": "Clarity practices: five core practices", "source_type": "public_teaching_material", "quality_tier": "C", "access": "public", "url": "https://antlerboy.com/library/files/talks/clarity-practices.pdf", "date": "2024-12-11", "notes": "Public author teaching deck connecting constructive conversation, clarity, reflection, culture shaping and intent in a learning and purposeful system. Public PDF linked on 2026-09-19; the earlier unpublished access description is superseded.", "creators": [ "Benjamin P Taylor" ], "doi": "", "isbn": "", "publisher": "Benjamin P Taylor public work library", "licence": "not_publicly_licensed", "archived_url": "", "content_hash": "", "review_status": "public_file_identity_checked", "last_checked": "2026-09-19", "public_link_status": "public_link" }, { "id": "src_practice_lab_systems_laws", "title": "Systems laws: test variety, feedback and local optimisation", "source_type": "practice_resource", "quality_tier": "A", "access": "public", "url": "https://transduction.systems/systems-thinking/practice/systems-laws/", "date": "2026-09-07", "notes": "Original fictional exercise. Basic examples of requisite variety, feedback delay and whole-system effects. The SCiO row is broader; this page does not claim to cover every law in a systems-laws course.", "creators": [ "The Necessary Tangle editorial practice pack" ], "doi": "", "isbn": "", "publisher": "The Necessary Tangle", "licence": "Original practice text CC BY-SA 4.0; external material retains source terms", "archived_url": "", "content_hash": "", "review_status": "original_material_and_source_boundary_recorded", "last_checked": "2026-09-07", "public_link_status": "public_link" }, { "id": "src_taylor_boxer_boundary_2026", "title": "What the boundary cannot carry alone, working redraft v3", "source_type": "working_paper", "quality_tier": "A", "access": "public", "url": "https://antlerboy.com/library/what-the-boundary-cannot-carry-alone/", "date": "2026-09-09", "notes": "Taylor and Boxer, 26 August 2026. All seven pages of the supplied manuscript inspected; not a peer-reviewed final article. The title page gives v3; the running footer retains v1.", "creators": [ "Benjamin P Taylor", "Philip Boxer" ], "doi": "", "isbn": "", "publisher": "Benjamin P Taylor public work library", "licence": "source terms unless otherwise stated", "archived_url": "", "content_hash": "", "review_status": "source_scope_checked", "last_checked": "2026-09-09", "public_link_status": "public_link", "connection_pass": "september_connections_2026" }, { "id": "src_taylor_vsm_lecture_2025", "title": "Benjamin Taylor VSM lecture", "source_type": "public_teaching_material", "quality_tier": "C", "access": "public", "url": "https://antlerboy.com/library/files/talks/viable-system-model-lecture.pdf", "date": "2025-05-10", "notes": "Public teaching presentation. Public PDF linked on 2026-09-19; the earlier unpublished access description is superseded.", "creators": [ "Benjamin P Taylor" ], "doi": "", "isbn": "", "publisher": "Benjamin P Taylor public work library", "licence": "not_publicly_licensed", "archived_url": "", "content_hash": "", "review_status": "public_file_identity_checked", "last_checked": "2026-09-19", "public_link_status": "public_link" }, { "id": "src_lib26_a9c290f694efcc45", "title": "Large-group processes", "source_type": "public_catalogue_record", "quality_tier": "C", "access": "public", "url": "https://antlerboy.com/library/files/talks/large-group-processes.pdf", "date": "2026-09-19", "notes": "Public Antlerboy manifest. PDF text indexed; located concept terms, not a full scholarly review. Identity and located teaching relationships are separated from automatic title matches and exact text mentions. A term appearing in a source is not proof of its definition, endorsement, influence, or logical dependence.", "creators": [ "Benjamin P Taylor" ], "doi": "", "isbn": "", "publisher": "Benjamin P Taylor public work library", "licence": "source terms unless otherwise stated", "archived_url": "", "content_hash": "", "review_status": "located_public_record", "last_checked": "2026-09-19", "public_link_status": "public_link", "connection_pass": "library_20260919", "year": "2024" }, { "id": "src_sp26_f455a61e7d99311f", "title": "Designing Social Systems in a Changing World", "source_type": "public_catalogue_record", "quality_tier": "C", "access": "public", "url": "https://doi.org/10.1007/978-1-4757-9981-1", "date": "2026-09-19", "notes": "Opening title and DOI; Crossref publisher metadata. Bibliographic identity matched; source text indexed. Identity and located teaching relationships are separated from automatic title matches and exact text mentions. A term appearing in a source is not proof of its definition, endorsement, influence, or logical dependence.", "creators": [ "Bela H. Banathy" ], "doi": "", "isbn": "", "publisher": "Springer US", "licence": "source terms unless otherwise stated", "archived_url": "", "content_hash": "", "review_status": "located_public_record", "last_checked": "2026-09-19", "public_link_status": "public_link", "connection_pass": "library_20260919", "year": "1996" }, { "id": "src_sp26_82aabbef7e96f5ee", "title": "Designing interagency responses to wicked problems: A viable system model board game", "source_type": "public_catalogue_record", "quality_tier": "C", "access": "public", "url": "https://doi.org/10.1016/j.ejor.2023.06.040", "date": "2026-09-19", "notes": "Opening title and DOI; Crossref publisher metadata. Bibliographic identity matched; source text indexed. Identity and located teaching relationships are separated from automatic title matches and exact text mentions. A term appearing in a source is not proof of its definition, endorsement, influence, or logical dependence.", "creators": [ "Pamela Sydelko", "Angela Espinosa", "Gerald Midgley" ], "doi": "", "isbn": "", "publisher": "Elsevier BV", "licence": "source terms unless otherwise stated", "archived_url": "", "content_hash": "", "review_status": "located_public_record", "last_checked": "2026-09-19", "public_link_status": "public_link", "connection_pass": "library_20260919", "year": "2024" }, { "id": "src_sp26_a63f52d3fe0bc7c0", "title": "Systems Approaches to Managing Change: A Practical Guide", "source_type": "public_catalogue_record", "quality_tier": "C", "access": "public", "url": "https://doi.org/10.1007/978-1-84882-809-4", "date": "2026-09-19", "notes": "Opening title and DOI; Crossref publisher metadata. Bibliographic identity matched; source text indexed. Identity and located teaching relationships are separated from automatic title matches and exact text mentions. A term appearing in a source is not proof of its definition, endorsement, influence, or logical dependence.", "creators": [], "doi": "", "isbn": "", "publisher": "Springer London", "licence": "source terms unless otherwise stated", "archived_url": "", "content_hash": "", "review_status": "located_public_record", "last_checked": "2026-09-19", "public_link_status": "public_link", "connection_pass": "library_20260919", "year": "2010" }, { "id": "src_sp26_b55bd7bc2eb7cb79", "title": "Governance for intelligent organizations: a cybernetic contribution", "source_type": "public_catalogue_record", "quality_tier": "C", "access": "public", "url": "https://doi.org/10.1108/K-01-2018-0019", "date": "2026-09-19", "notes": "Opening title and DOI; Crossref publisher metadata. Bibliographic identity matched; source text indexed. Identity and located teaching relationships are separated from automatic title matches and exact text mentions. A term appearing in a source is not proof of its definition, endorsement, influence, or logical dependence.", "creators": [ "Markus Schwaninger" ], "doi": "", "isbn": "", "publisher": "Emerald", "licence": "source terms unless otherwise stated", "archived_url": "", "content_hash": "", "review_status": "located_public_record", "last_checked": "2026-09-19", "public_link_status": "public_link", "connection_pass": "library_20260919", "year": "2019" }, { "id": "src_sp26_d247bb84f3b2c0fe", "title": "Improving practice in safeguarding at the interface between hospital services and children’s social care: a mixed-methods case study", "source_type": "public_catalogue_record", "quality_tier": "C", "access": "public", "url": "https://doi.org/10.3310/hsdr03040", "date": "2026-09-19", "notes": "Opening title and DOI; Crossref publisher metadata. Bibliographic identity matched; source text indexed. Identity and located teaching relationships are separated from automatic title matches and exact text mentions. A term appearing in a source is not proof of its definition, endorsement, influence, or logical dependence.", "creators": [ "Susan White", "David Wastell", "Suzanne Smith", "Christopher Hall", "Emilie Whitaker", "Geoff Debelle", "Russell Mannion", "Justin Waring" ], "doi": "", "isbn": "", "publisher": "National Institute for Health and Care Research", "licence": "source terms unless otherwise stated", "archived_url": "", "content_hash": "", "review_status": "located_public_record", "last_checked": "2026-09-19", "public_link_status": "public_link", "connection_pass": "library_20260919", "year": "2015" }, { "id": "src_sp26_a24718379b3ee4d2", "title": "Presencing the Future of Democracy and Governance", "source_type": "public_catalogue_record", "quality_tier": "C", "access": "public", "url": "https://doi.org/10.47061/jasc.v6i1.13060", "date": "2026-09-19", "notes": "Opening title and DOI; Crossref publisher metadata. Bibliographic identity matched; source text indexed. Identity and located teaching relationships are separated from automatic title matches and exact text mentions. A term appearing in a source is not proof of its definition, endorsement, influence, or logical dependence.", "creators": [ "Oliver Koenig", "Eva Pomeroy", "Megan Seneque", "Otto Scharmer" ], "doi": "", "isbn": "", "publisher": "Presencing Institute, Inc.", "licence": "source terms unless otherwise stated", "archived_url": "", "content_hash": "", "review_status": "located_public_record", "last_checked": "2026-09-19", "public_link_status": "public_link", "connection_pass": "library_20260919", "year": "2026" }, { "id": "src_sp26_987f525729b1e665", "title": "On Control and Communication: Self-regulation and Coordination of Actions", "source_type": "public_catalogue_record", "quality_tier": "C", "access": "public", "url": "https://doi.org/10.1007/978-3-642-19109-1_2", "date": "2026-09-19", "notes": "Opening title and DOI; Crossref publisher metadata. Bibliographic identity matched; source text indexed. Identity and located teaching relationships are separated from automatic title matches and exact text mentions. A term appearing in a source is not proof of its definition, endorsement, influence, or logical dependence.", "creators": [ "Raul Espejo", "Alfonso Reyes" ], "doi": "", "isbn": "", "publisher": "Springer Berlin Heidelberg", "licence": "source terms unless otherwise stated", "archived_url": "", "content_hash": "", "review_status": "located_public_record", "last_checked": "2026-09-19", "public_link_status": "public_link", "connection_pass": "library_20260919", "year": "2011" }, { "id": "src_u34_42_delay", "title": "The Equilibrium of Delay", "source_type": "public_source", "quality_tier": "B", "access": "public", "url": "https://42systemicreview.org/papers/the-equilibrium-of-delay", "date": "2026", "notes": "The review interprets Playford’s capital-works backlog through accumulated commitments, a planning/design constraint, and delayed work consuming delivery attention. Its proposed mechanism and capacity claims need comparison with the cited council evidence.", "creators": [], "doi": "", "isbn": "", "publisher": "Original author or publisher", "licence": "source terms unless otherwise stated", "archived_url": "", "content_hash": "", "review_status": "source_scoped_research_pass", "last_checked": "2026-10-24", "public_link_status": "public_link", "connection_pass": "update_20261024", "source_locator": "Executive Summary; Findings; System Framing and Method" }, { "id": "src_u35_beer_vsm_1989", "title": "The Viable System Model: its provenance, development, methodology and pathology", "source_type": "primary_text", "quality_tier": "A", "access": "public", "url": "https://kybernetik.ch/dwn/Viable_System_Model.pdf", "date": "1989", "notes": "Primary text opened and inspected. The cover says 1989; Appendix 2 explicitly gives page references to The Heart of Enterprise (1979). Do not silently identify this edition with the 1984 JORS paper. It is Beer's own methodological and historical account, not independent effectiveness evidence. Copyright 2002 Cwarel Isaf Institute.", "creators": [ "Stafford Beer" ], "doi": "", "isbn": "", "publisher": "Cwarel Isaf Institute, electronic edition 2002; cover dates the text 1989", "licence": "source terms unless otherwise stated", "archived_url": "", "content_hash": "", "review_status": "passage_checked_research_pass", "last_checked": "2026-10-29", "public_link_status": "public_link", "connection_pass": "depth_20261029", "source_locator": "Provenance, PDF pp. 3–4; On mapping and measuring complexity, pp. 6–8; The Viable System Model, pp. 10–11; Appendix 2, p. 16", "access_note": "Do not silently identify this edition with the 1984 JORS paper. It is Beer's own methodological and historical account, not independent effectiveness evidence. Copyright 2002 Cwarel Isaf Institute." } ], "evidence_locators": [ { "id": "ev_ashby_variety_definition", "source_id": "src_ashby_intro_cybernetics_1956", "locator": "chapters 7–8; official archive bibliography entry 56", "review_status": "research_pass_needs_editor" }, { "id": "ev_ashby_requisite_variety", "source_id": "src_ashby_intro_cybernetics_1956", "locator": "chapter 11, especially sections 11/7–11/13", "review_status": "research_pass_needs_editor" }, { "id": "ev_ashby_archive_chronology", "source_id": "src_ashby_archive_biography", "locator": "sections '1952–53 The Law of Requisite Variety' and '1952–56 An Introduction to Cybernetics'", "review_status": "research_pass_needs_editor" }, { "id": "ev_conant_ashby_theorem", "source_id": "src_conant_ashby_good_regulator_1970", "locator": "International Journal of Systems Science 1(2), abstract and pp. 89–97", "review_status": "research_pass_needs_editor" }, { "id": "ev_metaphorum_vsm_bases", "source_id": "src_metaphorum_vsm_2026", "locator": "The VSM in 1000 words, paragraphs 2-3", "review_status": "research_pass_needs_editor" }, { "id": "ev35_concept_requisite_variety_1", "source_id": "src_ashby_intro_cybernetics_1956", "locator": "Sections 11/5–11/11, especially 11/9", "review_status": "research_pass_needs_editor" }, { "id": "ev35_edge_e_fpcs_topic_034_concept_requisite_variety_1", "source_id": "src_ashby_intro_cybernetics_1956", "locator": "Ashby, sections 11/5–11/9; Conant and Ashby, theorem and proof, PDF pp. 8–9", "review_status": "research_pass_needs_editor" }, { "id": "ev35_edge_e_fpcs_topic_034_concept_requisite_variety_2", "source_id": "src_conant_ashby_good_regulator_1970", "locator": "Ashby, sections 11/5–11/9; Conant and Ashby, theorem and proof, PDF pp. 8–9", "review_status": "research_pass_needs_editor" }, { "id": "ev35_edge_e35_variety_transduction_1", "source_id": "src_u35_beer_vsm_1989", "locator": "Appendix 2, PDF p. 16, third principle", "review_status": "research_pass_needs_editor" } ], "reuse_note": "Preserve source attribution, scope, and review status. Source documents and evidence excerpts are excluded." }