Week 3: Your Brain Is Part of the Interface

How defaults, fake scarcity and social proof quietly steer decisions you thought you made yourself

8 March 2027

Designers don’t just design interfaces; they design decisions. This week supplies the vocabulary for saying so precisely: defaults, loss aversion, scarcity, social proof, commitment, cognitive load, choice overload, habit formation. Each one turns a vague complaint into a testable claim — “the website made me choose the expensive option” becomes “the website used a pre-selected default and visual emphasis to raise the odds of the expensive option,” and only the second version is something you could design against, or design with.

The same decision can read completely differently depending on how it’s worded — “lose your benefits” and “cancel subscription” describe the exact same click, but only one of them feels like giving something up. That’s not an accident of language; it’s a choice about how the option gets presented, made before you ever saw it.

Outline#

• the behavioural vocabulary: defaults, loss aversion, scarcity, social proof, commitment, cognitive load, choice overload, habit formation
• how the same decision reads differently as “lose your benefits” versus “cancel subscription”
• choice architecture: the layout of options is already a decision about the outcome
• turning a complaint into a mechanism claim
• Make Me Click It, this week’s session
• the Hate Catalogue closes today as Assessment 1 — next week starts Create