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Small site to explain System One Thinking
- Forks
- 3
- Last pushed
- Updated Sep 2026
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System One: An Interactive Guide
An interactive site by Sarah Drasner that explains System One thinking — fast, automatic judgments versus deliberate checking — and what that distinction means for software design, closing with the Jev × WebMCP Chrome extension as a case study.
- Stars
- 10
- Language
- JavaScript
- License
- APACHE-2.0
- Reading time
- 2 min
- Published by
- Community
- Author
- sdras
- Last verified
- Oct 2026
Used inJev for Software & DevTools
- Languages
- JavaScript
- Platforms
- Browser
- Capabilities
- Open source
Highlights
- Interactive guide to System One thinking: fast, automatic judgments, how they differ from deliberate checking, and what that means for software.
- Covers classification and scoring as software examples, plus thresholds, confidence, and checks between a prediction and an action.
- Final section uses the Jev × WebMCP Chrome extension as a case study: tool discovery, schema-derived questions, argument assembly, execution policy.
- Content-boundaries section draws on Daniel Kahneman's Nobel lecture and notes limitations of the analogy and of model predictions.
- Apache-2.0 JavaScript site: npm install, npm run dev locally, npm run build for a static build; live demo hosted on Netlify.
Quickstart
bash
npm install
npm run dev
npm run buildWatch out
README reviewed 2026-10-17; the digest truncates inside the content-boundaries section, so the complete source list for the psychology framing is not visible. The repo states no tests, benchmarks, or Node version requirement, and the live demo is a Netlify deployment.
Questions about this entry
Short answers drawn from the linked project or page.
A small interactive site by Sarah Drasner that explains System One thinking: fast, automatic judgments, how they differ from deliberate checking, and what that distinction implies for software design. The README frames it as an introduction rather than documentation.
Its final section uses the Jev × WebMCP Chrome extension as a case study, showing how a specific model and a browser tool interface implement tool discovery, schema-derived questions, argument assembly, and execution policy.
Clone the repository and run npm install, then npm run dev for a local server or npm run build to produce a static build. The digest shows no other prerequisites besides a Node.js toolchain.
Fast judgments and deliberate reasoning as modes of thinking, classification and scoring as software examples of bounded judgments, thresholds and confidence checks between a prediction and an action, and combining independent judgments into a workflow.
No — the README says the psychological introduction draws on Daniel Kahneman's Nobel lecture and the guide includes a section on limitations of the analogy and of model predictions, so the mapping is presented as an analogy rather than an equivalence.
Sarah Drasner (sdras) built it. GitHub metadata shows 9 stars, 3 forks, JavaScript, Apache-2.0, created 2026-09-19 and last pushed 2026-09-26.
Yes — the README links a live demo at system-one-explainer.netlify.app. There is no API key or backend; the repo is a front-end build with npm scripts.
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