Three-Legged Truth Stool
Triangulate ideas across science, history, and lived practice
- Difficulty
- Moderate
- Time to result
- ~weeks to results
- Steps
- 5
- Confidence
- 96%
The Three-Legged Truth Stool tests a proposed principle against three independent evidence streams: modern empirical science, history and ancient wisdom, and concrete daily practice. A finding supported by only one stream may be fashionable, context-bound, or impractical; support from two streams is better but still unstable. The strongest candidates recur in peer-reviewed research, across enduring traditions, and in the behaviour of people who embody the desired outcome. Collect observations from each leg, cluster recurring themes, and repeatedly narrow the list until only ideas with three-way support remain. The output is not certainty, but a sturdier foundation for teaching, writing, or acting than any single source can provide.
Origin
Brad Stulberg used this research structure for The Practice of Groundedness, reducing thousands of note cards into six principles that appeared in science, ancient wisdom, and present-day practice.
Core principles
- 01One evidence source is too fragile
- 02Durable principles recur across different domains
- 03Practical usefulness matters alongside intellectual support
How to run it
- 1
Define the claim
State the principle you want to test and the outcome it is supposed to produce.
Pro tip Make the claim specific enough that each evidence stream can contradict it.
- 2
Check modern science
Review peer-reviewed studies, meta-analyses, and other empirical findings relevant to the claim.
Watch out Do not treat one study as a settled conclusion.
- 3
Check enduring wisdom
Look for the same mechanism across history and traditions such as Buddhism, Taoism, or Stoicism.
Watch out Distinguish enduring themes from ideas that worked only in one era.
- 4
Check daily practice
Talk to people achieving the desired outcome and identify what they repeatedly do in real life.
Pro tip Ask about behaviour, not just beliefs.
- 5
Keep the intersections
Cluster the findings and retain only principles that repeatedly appear in all three streams.
Watch out A compelling idea with a missing leg remains wobbly.
In the wild
A founder considers making daily walks part of the company routine. She reviews movement research, checks how older mind-body traditions treated physical activity, and interviews sustainable operators about their routines. Because all three streams support regular movement, she pilots the practice rather than relying on one productivity influencer's claim.
→ The decision rests on converging evidence instead of a single anecdote.
Common mistakes
Trusting one evidence stream
A scientific result, ancient maxim, or successful person's habit can each mislead when used alone.
Counting mentions instead of mechanisms
Surface similarity does not prove that the same causal principle appears across all three legs.
Is it for you?
Best for
Researchers, writers, and operators evaluating broad claims about human behaviour.
Not ideal for
Fast, low-stakes decisions where deep triangulation would cost more than an error.
From the transcript
“one leg of that stool was what i'll call modern empirical science”
“the second leg of that stool is history and ancient wisdom”
“the third leg of the stool is daily concrete practicality”
From the episode
Brad Stulberg: Six Mental Health Principles Entrepreneurs Need to Beat Burnout
Brad Stulberg