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Tools for thinking, to keep
One-time prices, instant download, files you own. 7-day refund if it isn't for you.
PDF + EPUB
The Mentarium Field Guide
60 Mental Models for Clearer Thinking and Better Decisions
$14$19
- 60 mental models, 1 to 2 pages each: in one line, when to use it, trigger questions, an example, the trap
- The 25 biases that break good decisions, each with the model that fixes it
- 12 Model Stacks for real situations: quitting a job, hiring, investing, moving cities and more
Coming soon
Details
Claude skills (SKILL.md) + ChatGPT instructions
Mentarium Thinking Skills
12 skills that make Claude and ChatGPT think with mental models
$29
- 12 Claude skills (SKILL.md) for Claude.ai, the Claude apps and Claude Code
- The same 12 as ChatGPT Custom GPT / Project instructions, plus a knowledge file with the Mentarium frameworks
- Install guide for both, in plain steps
Coming soon
Details
Obsidian vault (Notion edition coming soon)
The Mentarium Decision Journal
Log decisions, review them, and see how well calibrated you are
$29
- An Obsidian vault: plain Markdown files you own, no account
- A decision template guided by the Decision Loop, with the Decision Weight Score
- Review Queue: decisions whose review date has come
Coming soon
Details
Bundles
Field Guide + Decision Journal
$44
Thinking Skills + Field Guide
$49
Mentarium Complete
$69 · save $3
Bought before? Resend my download links. The Decision Coach for Claude and ChatGPT is free.