[5] According to critic Ryan Jay Friedman, Lee's writing in the 1910s argued that Christian education was similar to mass media including advertising, in that both attempted to persuade people to "choose a particular 'good'".

[5] Jo-Anne Pemberton compares Lee's The Voice of the Machines: An Introduction to the Twentieth Century (1906) with the works of Filippo Tommaso Marinetti and futurism.

[7] When Crowds was released in 1913, Lee wrote in a letter to Theodore Roosevelt that he hoped that it would be "the text-book of the Progressive Movement".

[10] Lee was "a frequent contributor of reviews to the Critic and other periodicals and wrote books on religion, modern culture, and physical fitness".

[12] According to Leonidas Warren Payne Jr., Lee was "a milder, saner sort of twentieth-century Carlyle, interpreting human nature in new terms for the new age".