[...] language is variable. Two individuals of the same generation and locality, speaking [...] the same dialect and moving in the same social circles, are never [...] at one in their speech-habits.
- Sapir (1921), a pag.147

The individual variations are swamped in [...] by certain major agreements- say of pronounciation and vocabulary- which stand out very strongly when the language of the group as a whole is contrasted with that of the other group.
- Sapir (1921), a pag.147

What keeps the individual's variations from rising to dialectic importance [...] is chiefly that they are silently 'corrected' or canceled by the consensus of usage .
- Sapir (1921), a pag.148

Language exists only in so far as it is actually used- spoken and heard, written and read. What significant change take place in it must exist, to begin with, as individual variations.
- Sapir (1921), a pag.154