I have always understood that language was a critical element of cultural
identity, witness the ardor with which various European nationalist groups
insist that their dialect is quite distinct from that of their neighbors -
a separate language, in fact - but I can't think of any good quotes on the
subject. I could easily make some up, like "You are what you speak." Or,
"If you can't you can't talk the talk, how can you even think about walking
the walk?" (Too wordy; needs work!)