Triangulation

The discipline of building a thesis from multiple, cross-checking sources rather than trusting any single one. In How To Read a Book Kyle tags it against Adler’s “first rule of reading history” — “it is necessary to read more than one account of the history of an event or period if we want to understand it” — and again against the syntopical-reading rules and the biography rule (“read as many biographies of him as you can find, including his own”). It pairs with Progressive Summarization and the “live the library” frame as the actual method of multi-source reading.

In Talent (Book), triangulation becomes an evaluation discipline: Tyler Cowen and Daniel Gross’s “In which areas might this work? Might this not work? When does this work or not work?” — what they call looking for the cross-sectional variation. Kyle tags this verbatim as “Triangulation”: if you don’t understand when and where a claim is wrong, you don’t understand the claim. The same move appears in Equity Research (thesis-building from multiple sources, against the disclosure regime public markets supply) and in the Open-Source Knowledge - Research notes, where Kyle frames it as “What do you have to believe?” / “What gives you the right to believe?” — a single Glassdoor review or a team in sales-mode isn’t enough; you need corroborating angles because “you don’t know what you don’t know.”

Where this appears

• How To Read a Book — Adler’s “read more than one account” rule for history, biography, and syntopical reading; Kyle’s recurring “Triangulation” tag.
• Talent (Book) — Cowen/Gross’s cross-sectional-variation question (“when does this work or not work?”) as a talent-evaluation discipline.
• Equity Research — analytical method for constructing an investment thesis from multiple sources.
• Open-Source Knowledge - Research — “What do you have to believe?” / what gives you the right to believe, against single-source evidence.