In 1990s, Langan became involved in the IQ society subculture, particular in the Mega Society news letters of Ronald Hoeflin and the social world of Rick Rosner (Noesis editor).
In 1991, Langan, in his “Prologue to Buffoonery” letter, was promoting his so-called "cognitive theory model of the universe", the gist of which being an attempt to prove the existence of good via Boolean algebra and self-motion theory.
In Nov 1999, Esquire magazine, in their genius issue, depicted Langan with the title "Smartest Man in America", which included an Gεπ1us Tεst IQs, made by test makers: Jim Ferry, Nik Lygeros, Bill McGaug, Heather Preston, Andreas Rottlier, John Scoville, Tommy Smith, and Wahl Patrick, purporting to yield a ceiling IQ of 160.
In Dec 1999, the show 20/20 did an interview special on Langan, entitled “The Smart Guy”, during which Bob Novelly, American neurophsychologist, supervised Langan in taking a two-hour IQ test, commenting that Langan's score was the highest individual he has measured in 25-years.
In 2001, Errol Morris filmed a 30-minute interview with Langan entitled “The Smartest Man in the World”, wherein Langan claims that based on an Omni Magazine intelligence test, that his IQ is 190 to 210, and that he has seen farther than anyone come before him.
In 2008, Malcolm Gladwell, in his Outliers: the Story of Success, featured Langan and his story, as an example of a social outlier.
Quotes | By
The following are quotes:
- “My IQ is somewhere between 190 of 210. I am closer to absolute truth than any man who has come before me.”
- — Christopher Langan (2001), "Interview with Errol Morris", First Person Series
- “An atheist who considers himself “rational” has no choice but to deny that justice exists in any necessary sense, thus voiding any responsibility to explain its absence. And as the concept of justice flies out the window, so does any en-force-able basis for morality, thus reducing phrases like “moral atheist” and “atheistic morality” to meaninglessness.”
- — Christopher Langan (2017), “Atheist justice question”, Quora, Jul 17 
- Langan, Christopher. (1991). “Prologue to Buffoonery”, Noesis, The Journal of the Noetic Society, 62, Jun.
- Anon. (2020). “IQ Comparison: Smartest People” (YT), Beauty of Data, May 9.
- Sager, Mike (1999). “The Smartest Man in America” (WB), Esquire, Nov.
- Ferry, Jim, Lygeros, Nik; McGaug, Bill; Preston, Heather; Rottler, Andreas; Scoville, John; Smith, Tommy; and Wahl, Patrick. (1999). “Gεπ1us Tεst”, Esquire (Ѻ), Nov 1.
- Morris, Errol. (2001). “Interview: Christopher Michael Langan” (YT), First Person series; EricChanning7, 2011.
- Langan, Christopher. (2017). “Atheist justice question”, Quora, Jul 17.
- Langan, Christopher. (2002). “The Cognitive-Theoretic Model of the Universe: a New Kind of Reality” (WB), MegaFoundation.org, 2015.