Synthesized answer
The provided passages do not contain information about the evidence the author provides in "Understanding Media: The Extensions of Man." The passages only include the title and publication information of the book [1]. Therefore, it is not possible to answer what evidence the author provides based on the given text.
Synthesized from the book passages below. Chat with the book on Feynman for follow-up.
From the book
Title: Rare Marshall McLuhan / Understanding Media The Extensions of Man 1964 - NY by Marshall McLuhan