Surface Form & Underlying Structure

Abstractions about the gap between a system's visible surface and its true underlying structure — controlled-vocabulary naming (preferred labels, cross-references, subject headings) that route many surface forms to one canonical concept, and interface failures (focus order, information scent, screen-reader ambiguity) where surface cues misrepresent it.

23 abstractions in this family — domain-specific abstractions that sit near one another in structural-signature space (k-means over structural-signature embeddings). Each is shown with its short description.

• Accessibility — The design commitment to keep a system perceivable, operable, understandable, and robust for the full distribution of intended users including the sensory, motor, cognitive, and infrastructural tails — by designing to those tails rather than to the median.
• Aspect Qualifier — Attach a controlled modifier from a small closed list to a subject descriptor so the indexed claim names a topic in one specific sense — Aspirin/adverse effects, not aspirin-as-such — factoring topic from aspect to gain precision without vocabulary bloat.
• Authorized access point — Assign each entity one rule-built, human-readable string that serves at once as heading, retrieval key, and cross-reference anchor — with a disambiguating qualifier carried in the string so two namesakes never collapse into one index entry.
• Controlled Descriptor — Substitute one governed preferred term from a maintained vocabulary for whatever words a resource used, so every resource on a topic retrieves through the same descriptor regardless of the author's surface phrasing.
• Cross-reference Relation — Connect two controlled-vocabulary entries with a typed directed half-edge drawn from a small closed inventory (USE, UF, BT, NT, RT, SA), each carrying a stipulated direction, symmetry, inverse-pairing obligation, and system action — turning a flat term list into a maintainable navigable graph.
• Discoverability — Measure the degree to which a system's actions and features can be located through perception and exploration alone — a property of the artifact, not the user — separating capability from findable capability and locating unfound features as a design defect.
• Entry Term Alias — Curate a non-preferred surface form — synonym, abbreviation, colloquialism, superseded name — as a silent, non-indexing bridge that routes many-to-one to a canonical descriptor, so users arrive at one place however they name the concept.
• Focus-Order Failure — The accessibility defect in which an interface advances programmatic focus (Tab navigation, screen-reader linearization) in a sequence that diverges from the task's semantic order — invisible to visual review, and sometimes placing a confirmation control before the content it confirms.
• Functional Fixedness — The cognitive bias in which encoding an object under its conventional category label crowds out inspection of its raw physical properties, blocking the solver from a non-conventional use the problem needs and the object's properties would permit.
• Hidden Label — A string attached to a controlled-vocabulary concept that is indexed for retrieval but withheld from display — so a user typing a typo, deprecated synonym, or embarrassing prior name finds the concept while the result still shows only the sanctioned preferred term.
• Information-Scent Failure — Diagnose a navigation failure as the surface cues a user reads before clicking — link text, labels, snippets — failing to predict the destination's content, so the user invests a click on a wrong prediction and backtracks, hunts, or abandons.
• Microcopy Ambiguity — The HCI failure where a terse interface label admits more than one reading, so the user decompresses it against a prior different from the designer's and acts correctly on the wrong interpretation.
• Mooers's law — The retrieval-system regularity that a system tends not to be used whenever having the information is more troublesome than not having it — adoption governed by the per-query cost-benefit ratio against a substitute, not the content's absolute value.
• Near-equivalence Mapping — Bridge two concepts in different controlled vocabularies with a declared correspondence that carries an explicit, typed loss-risk on the bridge itself, so consumers can route each substitution on whether their use falls in the safe zone.
• Precoordinated Heading — Fuse topic, place, period, and form into one canonical subject string at indexing time so users retrieve by matching a whole browsable label, trading expressiveness and easy schema evolution for that browsability.
• Preferred label — Among the many surface forms that could name one concept, have a vocabulary authority choose, declare, and protect exactly one per language as the form the vocabulary speaks in its own voice, demoting the rest to aliases recognized at input but suppressed at output.
• Primitive Obsession — The code smell of representing domain concepts that carry structural commitments — units, valid ranges, well-formedness, identity — as bare primitives like int or string, so the type system cannot enforce the distinctions and they survive only as validation duplicated at every callsite.
• Responsive-Layout Breakage — Diagnose the silent UI failure where an interface's content survives a viewport, device, or locale transformation but its layout-encoded meaning — priority, adjacency, hierarchy, above-the-fold prominence — is lost, so a passing content-accessibility check actively conceals the defect.
• Robust Accessibility — Author web content so its load-bearing meaning lives in structural markup and the accessibility tree rather than in presentational accidents, so any current or future assistive technology — including ones the author cannot test against — can recover the intent through the same shared API.
• Screen-Reader Ambiguity — An interface's visual structure carries semantic information never encoded into the machine-readable accessibility tree, so an assistive-technology user — navigating only that projection — encounters an interface stripped of the organization a sighted user relies on.
• Script Activation — Trigger, from a single environmental or linguistic cue, the loading of a stored ordered event sequence with role and prop slots and default fillers, which then gap-fills comprehension, pre-allocates processing, and scaffolds action at once.
• Subject Heading String — Assemble a main topical heading with an ordered sequence of controlled subdivisions — topical, geographic, chronological, form — into one concatenated string at indexing time, eagerly committing a multi-facet intersection as a single citable, browsable, retrievable token.
• Theme Reification — Diagnose the qualitative-analysis failure where an analyst-authored thematic label is treated as a real entity in the world — the grammatical subject migrating from 'I grouped these utterances' to 'participants have this need' — by testing whether provenance to specific quotations survives.