The main concept of McLuhan's argument (later elaborated upon in "The Medium is the Massage") is that new technologies (like alphabets, printing presses, and even speech itself) exert a gravitational effect on cognition, which in turn affects social organization: print technology changes our perceptual habits ("visual homogenizing of experience"), which in turn affects social interactions ("fosters a mentality that gradually resists all but a... specialist outlook"). According to McLuhan, the advent of print technology contributed to and made possible most of the salient trends in the Modern period in the Western world: individualism, democracy, Protestantism, capitalism and nationalism. For McLuhan, these trends all reverberate with print technology's principle of "segmentation of actions and functions and principle of visual quantification."