April 5, 1962, McLuhan to E. T. Hall
M notes he is working on “Understanding Media and Politics” [what became Understanding Media] and that he has also been working on Heisenberg’s Physics and Philosophy. He also says that “The Copenhagen school talks my language.” He adds: Heisenberg's "distinction between rotational and non-rotational systems as creating quite distinct spatial configurations corresponds exactly to my divisions between centre-margins and centres without margin systems." “Thus, the centre-margin system is explosive (fission), and the centre-without-margin system is implosive (fusion). The centrifugal system corresponds to that outtering of sense and faculty, with all the consequent products familiar in fission, whereas implosion results in quite different products. It seems to be that an oral society is imploded, and a literate one exploded…."