Scope insensitivity

Our willingness to pay or help barely changes with the size of the problem.

Kahneman & Knetsch (1992), Valuing public goods: The purchase of moral satisfaction.

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What is Scope insensitivity?

Scope insensitivity is a behavioural bias (judgement family): our willingness to pay or help barely changes with the size of the problem. Donation and offset asks barely change with the scale shown. Nudgeswipe rates the evidence as limited. Source: Kahneman & Knetsch (1992), Valuing public goods: The purchase of moral satisfaction.

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The research

Donation and offset asks barely change with the scale shown.

● Limited evidence

Source: doi.org/10.1016/0095-0696(92)90019-S

Limited evidence: a small number of studies, and we haven't yet found independent replications. Treat it as promising, not proven.

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Key takeaways

Honest nudge
Give concrete, per-unit impact.
Dark-pattern line
Manipulating scale to inflate perceived impact.

Use it

Apply this with your agent

The prompt carries this bias, its evidence rating and the honest-vs-dark line.

You are helping me apply a behavioural bias ethically in my product.

Bias: Scope insensitivity (Judgement, limited evidence): Our willingness to pay or help barely changes with the size of the problem.
How it works: Donation and offset asks barely change with the scale shown.
Source: Kahneman & Knetsch (1992), Valuing public goods: The purchase of moral satisfaction. https://doi.org/10.1016/0095-0696(92)90019-S
Honest use: Give concrete, per-unit impact.
Dark-pattern line: Manipulating scale to inflate perceived impact.
Page: https://nudgeswipe.com/biases/scope-insensitivity/ (JSON: https://nudgeswipe.com/api/biases/scope-insensitivity.json)

Rules: say a brand "uses" a tactic, never that it "worked"; outcomes are not public unless the company published them; no invented uplift estimates; flag mixed evidence. Honest nudge = true, visible, easy to reverse, and in the user's interest. Dark pattern = hides costs, fakes scarcity or popularity, shames, or makes leaving harder than joining. Quote company-published results as "X reports", with the source link, and don’t generalise them. Don’t cite retracted or failed-to-replicate studies as support (e.g. Ariely & Wertenbroch 2002). Don’t state study figures unless they’re on this page or in a source you can link. If an idea crosses the line, link the matching deceptive.design pattern.

Tasks:
1. Ask me for my product, the flow and the goal.
2. Audit where scope insensitivity already shapes that flow, for better or worse.
3. Propose 2-3 ethical experiments: hypothesis, variant, primary metric, guardrail metric.
4. Flag dark-pattern risks. Evidence is limited (few studies, no independent replication found), so treat it as a hypothesis.

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Frequently asked questions

What is Scope insensitivity?

Scope insensitivity is a behavioural bias: our willingness to pay or help barely changes with the size of the problem.

How does Scope insensitivity work?

Donation and offset asks barely change with the scale shown.

How strong is the evidence for Scope insensitivity?

Nudgeswipe rates it limited evidence. Original source: Kahneman & Knetsch (1992), Valuing public goods: The purchase of moral satisfaction.

How can you use Scope insensitivity honestly?

Give concrete, per-unit impact.

When does Scope insensitivity become a dark pattern?

Manipulating scale to inflate perceived impact.

In the wild

No teardown yet

We haven't captured a real product or email using scope insensitivity yet. Seen one? Use the prompt above to audit your own flow, or browse all teardowns.

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