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I Built Paul Graham's Intellectual Captcha Idea

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PG has posted about improving social networks using something like an "intellectual CAPTCHA" many times [1][2][3][4] - "Make users pass a test on basic concepts like the distinction between necessary and sufficient conditions before they can tweet."I felt the same way. So I built one using a mix of simple math, logic, and Twitter/X Community Noted posts. Try sample questions here - https://mentwire.com/sample - without signing up.- Invites are temporarily open to HN users.- Onboarding test + one daily question before accessing feed, post or reply.- Posts authors are anonymous until upvoted or downvoted, forcing evaluation of content on merit.- Face ID (on-device only) to post/reply, pangram checks for AI text.Sourcing good questions turned out to be much harder than I thought. If you have suggestions to scale this, I would love to hear. Eventually, could be gated across disciplines/topics to get a competence × interest graph instead of the pure interest graph of today's social networks.[1] https://x.com/paulg/status/1235949761359904768 [2] https://x.com/paulg/status/1576517990182359040 [3] https://x.com/paulg/status/1514979883948126209 [4] https://x.com/paulg/status/1505842647319126016Repost from https://news.ycombinator.com/item?id=47577829.This link contains a full quiz and linked directly to sample to try without signing up.

HN · launched Apr 6, 2026 · 29 upvotes (top 21%) · 0 views

Niche: bot detection and captcha software · 32 launches, 5 in the last 7 days · Explore this niche →

Category and tags

  • Security
  • Vertical SaaS
  • B2C
  • Not AI
  • Hobby / open-source project

Visit website ↗ Source listing ↗

Could you build this?

Yes A web quiz app testing basic logical or philosophical reasoning concepts can be implemented in a day with a standard web stack, either with static questions or dynamic LLM-generated logic puzzles.

Discussion

20 comments analyzed.

Competitors

Other products that read as similar to this one : 234 launches clear the similarity bar, closest 8 shown.

Attention rank: #47 of 235 (itself plus its competitors, highest first, normalized so YC and Product Hunt are compared fairly).

Launched 159 days after the earliest competitor.

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