Johnson introduces the concept of the “slow hunch” through the story of FBI agent Ken Williams and his “Phoenix Memo” from July 2001. This memo warned about potential terrorist activity involving flight schools, specifically mentioning Osama bin Laden sending students to US aviation universities. Johnson presents this as an example of a valuable idea that failed to gain traction or connect with other relevant information, partly due to the FBI’s outdated information systems and organizational structure.

The chapter elaborates on the notion of hunches needing to collide with other hunches to become fully formed ideas. Johnson illustrates this by describing how Williams’s memo, if connected with information about Zacarias Moussaoui’s suspicious behavior at a flight school in Minnesota, might have provided enough evidence to prevent the 9/11 attacks. He explains that Moussaoui’s arrest and the subsequent struggle to obtain a search warrant for his laptop represented another crucial hunch that, if combined with Williams’s insights, could have uncovered direct connections to the 9/11 hijackers.

Johnson argues that environments like cities and the internet foster innovation because they allow for the easy flow of information and connection of partial ideas. He describes these as “liquid networks” that provide a kind of “dating service” for promising hunches, helping to complete ideas by connecting disparate pieces of information (75).