Math and logic riddles. Sometimes unnervingly tricky. Highly addictive.

From Weekly Filet #237, in June 2017.

The Riddler

FiveThirtyEight

💔 Some older links might be broken — that's the state of the web, sadly. If you find one, ping me.

You might also like

Paperclips

Decision Problem

Cards Against Originality

Cards Against Originality

Cards Against Originality

The New York Review of Video Games

The New York Review of Video Games

Parable of the Polygons

Parable of the Polygons

Explore more →

Explore collections

Making Sense of the Climate Crisis 41 links Making Sense of Artificial Intelligence 40 links All-time favourites 20 links The Stuff Our Modern World Runs On 13 links The Art of Thinking (Differently) 29 links Bingeworthy Podcasts & Episodes 36 links Stories, too good to put down 16 links

Book recommendations

2025 Book Club Books curious minds wished they discovered sooner Our most popular crowd-curated book recommendations thus far. Read the post →

Book Club illustration

Weekly Filet Book Club All recommendations from previous editions, at a glance. Find your next read → 📚 David's Bookshelf The books that shaped how I see the world and inform how I think and act. Browse the bookshelf →