TimPenner.ca

Extensionism is the fundamental tenet that media are not just simple appliances with which we solve simple little problems (like toasters), nor does the usual definition of media as in news media present a satisfactory view. Media are, by definition, extensions of our physical, psychic and social ourselves; we remake ourselves through them.

I'll not say more here, as extensionism is so straightforward and pervasive (in this work) and elsewhere in social science. Google extensionism to see more.

BTW, I've worked the word media to death in numerous articles. Please see (especially) The Toolshop Story and Intelligence Amplification and search for media to see where else it takes you.