Week 07 · Foundations

Door 1

Push or pull — see what happens.

Door 2

Push or pull — see what happens.

Door 3

Push or pull — see what happens.

Door 4

Push or pull — see what happens.

Push. Or Pull.

Four doors. Nothing here explains itself in words — try each one before you read another sentence. Tap Push or Pull below each door and see what actually happens.

Predict

Below are two panels, drawn to be pixel-identical. One is a real button; tapping it does something. The other is a static picture of a button and does nothing at all. Which one is the button?

Experience

The Affordance Dial

One element. Seven signifiers. The affordance never changes.

Below is a single button, exactly as clickable at every setting as it is at every other. Turn every signifier off and tap it — it still works. Turn them back on, one at a time, and watch the readout climb. The point of this dial is the gap between its two stable numbers: Affordance, which never moves, and Perceived affordance, which moves on every toggle.

The affordance dial

Same element throughout — only its signifiers change

Tap it — every setting above still works.

Affordance: Yes — always; the click has worked at every setting, all along
Signifiers active: 0 / 7; what you just toggled
Perceived affordance: 6%; modelled — see below

Perceived affordance is modelled, not measured: a 6-point baseline plus each active signifier’s weight (label 22, fill 16, shadow 14, outline 12, hover motion 10, underline 9, cursor 7), capped at 96 — no signifier set makes a control certain to every first-time user. The weights are this build’s own illustration of the dossier’s qualitative claim that every capability needs a perceivable cue (Affordance Theory Claude.md, §2.1); they are not a cited figure. Cursor and hover motion are desktop-only signifiers — try them with a mouse, not a thumb.

Concept

Three Words, Not One

“Affordance” gets used to mean roughly “how something looks.” That usage is a corruption of the term, and Don Norman said so about his own earlier writing.

James Gibson coined affordance in 1966 and developed it through 1979 to mean something relational and entirely independent of anyone noticing it: a stair affords climbing to an adult and not to an infant, and it affords that whether or not either of them ever looks at it. Norman imported the word into design in 1988 and narrowed it, on arrival, to what a person can readily perceive — but by 2008 he had watched the design community flatten it further still, into a synonym for visual style. His fix, folded into the 2013 edition of The Design of Everyday Things, split the word cleanly in two.

Affordance is the capability — real, in the code or the mechanism, whether or not anyone ever finds it. Signifier is the perceivable cue that announces it: a border, a shadow, an underline, a label. Perceived affordance is what a first-time user concludes from that cue, which may or may not match the truth. “Affordances determine what actions are possible. Signifiers communicate where the action should take place. We need both.”

That quote is Norman’s, attributed to the 2013 revised edition of DOET via Wikipedia’s Affordance article; it was not independently checked against the print text this session, so it is graded secondary below rather than verified. Norman’s own 2008 line — “part of the blame lies with me: I should have used the term ‘perceived affordance’” — was checked directly against jnd.org and is graded verified.

Deconstruction

Four Steps, Not One Origin Story

The theory did not arrive fully formed. It was corrected in public, twice, by the same person.

One note before you scroll the steps below: the popular story that the phrase Norman door comes from Don Norman getting stuck at a specific hotel door in Normandy does not check out. No source reachable for this piece corroborates it, and the likely explanation is a pun on his own surname that calcified into folklore. What is verifiable is narrower and, honestly, more useful: Norman spent DOET describing door failures in general, the phrase attached to that pattern afterward, and the pattern itself survives the correction untouched.

Year

1979After

1979 — Ecological affordances

The affordances of the environment are what it offers the animal, what it provides or furnishes, either for good or ill.

J. J. Gibson, 1979

Gibson's affordances are relational and observer-independent: a stair affords climbing to an adult and not to an infant, and it affords that whether or not anyone ever notices — affordances "exist whether or not they are perceived, signaled, or even physically usable." Nothing here is yet a design instruction. It is a claim about the world.

Real World

Two Ways to Be Wrong

A gap between the real and the perceived can point in either direction, and both directions have names.

A false affordance is full signifier over empty affordance — a card with every cue a button should have, wired to nothing. A hidden affordance is the mirror image — real capability, zero cue, discoverable only by accident or trial. Drag between the two below, then tap each one and see for yourself which is which.

Upgrade your plan

Raised. Bordered. Shadowed. Every cue says tap me.

View pricing details

Plain text. No underline, no colour, no cursor cue.

This false/hidden pairing, plus a third category — correct rejection, an honestly static element nobody mistakes for a control — is drawn from W. W. Gaver’s 1991 HCI taxonomy. It appears in this topic’s GPT research file, not the Claude file this build otherwise follows, and was not independently re-fetched from Gaver’s original paper this session — graded secondary below.

Experiment

Strip It Yourself

Every signifier below is doing a specific, nameable job. Remove one and the ledger tells you exactly what a first-time user loses.

One of the six is not a signifier at all — it is decoration wearing a signifier’s clothes. Find it by removing everything and watching which removal costs nothing.

✦ Welcome back

you@example.com

Password

••••••••

Must be at least 8 characters

Tap any signifier above to strip it. Watch what a first-time user loses.

0/6 removed

Challenge · Six elements

Open

Mark each of the six elements below Interactive or Not interactive, using only what you can see. You can change an answer after you see why it was wrong.

0 / 6 matched

Two are honest, one is a correct rejection, two are traps in opposite directions, and one is the dossier's own literal example.

Insight

An affordance you cannot perceive is not there for the user.

Every door, panel, dial setting, and mismarked element above was the same argument told six different ways: the system can be perfectly capable and the interface can still fail completely, because capability was never the thing users respond to. They respond to what they can see, and what they can see is a design decision, made or skipped, on every single element you ship.

Mental model

Whenever an interface gets called “unintuitive”,

look for the specific gap between what is actually possible and what is visibly signified — not a training gap in the user,

because an affordance nobody can perceive is functionally identical to an affordance that does not exist, and the fix is always the signifier, never a tooltip explaining it.

TomorrowPick one screen you shipped. For every interactive element, name its signifier out loud. Any element where you hesitate is a Norman door waiting for someone else to find it.

End of experience

← Back to the constellation

Push. Or Pull.

The Affordance Dial

Three Words, Not One

Four Steps, Not One Origin Story

Two Ways to Be Wrong

Strip It Yourself

Where this idea goes next

Push. Or Pull.

The Affordance Dial

Three Words, Not One

Four Steps, Not One Origin Story

Two Ways to Be Wrong

Strip It Yourself