The thinking you used to do before reaching for AI.
Is it still there?
Zanshin is a reasoning benchmark for engineers who use AI constantly — built to notice if independent thinking is quietly getting weaker underneath the speed.
You reach for AI before you've even thought about it. You use its output without checking it. You don't remember what it wrote because you never really processed it. None of this feels bad in the moment — it feels like speed.
What it measures
Syllogistic reasoning
deductive logic
Fermi estimation
sizing problems under uncertainty
Argument evaluation
spotting weak reasoning, like code review
Causal reasoning
root-cause thinking, debugging logic
How it works
01
Take a 5-minute benchmark, three times a week
02
See your score and trend by domain, not one vague number
03
Get a specific insight when a pattern and a dropping score actually line up — never a guess
Zanshin measures. It doesn't diagnose, and it doesn't promise to fix anything.
It's a place to keep your reasoning active — the same way a gym doesn't promise to make you healthy, it gives you somewhere to do the work.