Robert Logan, a Canadian physicist and media environmentalist, co-authored a book with McLuhan on the transition from physics to communication and media theory, and completed his theoretical innovation in defending, inheriting and developing McLuhan's media theory. In the process of crossing many liberal arts disciplines, a unifed theory of human brain, language, mind, information and culture has been formed, and a mental extension model of “mind = brain + language + culture” has been put forward, that is, a cognitive model of human being. In the process of synthesizing many liberal arts and sciences, he put forward symbolic theory and Paninformation theory and became a famous interdisciplinary theorist.