[...] the single significant elements of speech are the symbols of concepts [...]
- Sapir (1921), a pag.13

I am inclined to believe that [...] even the lowliest developments of material culture [...] were not strictly possible until language, the tool of significant expression, had itself taken shape.
- Sapir (1921), a pag.23

It happens occasionally that the single sound is an independently significant element (such as French 'a' 'has' and 'à' 'to' or Latin 'i' 'go!'), but such cases are fortuitous coincidences between individual sound and significant word.
- Sapir (1921), a pag.24

The voiced sounds are the most clearly audible elements of speech. As such they are the carriers of practically all significant differences in stress, pitch, and syllabification.
- Sapir (1921), a pag.49

[...] there is [...] an inherent tendency in English, at the time such forms as geese came into being, for the utilization of vocalic change as a significant linguistic method.
- Sapir (1921), a pag.60

In the Athabaskan languages there are not infrequently significant alternations of accent, as in Navaho 'ta-di-gis' 'you wash yourself' (accented on the second syllable), 'ta-di-gis' 'he washes himself' (accented on the first).
- Sapir (1921), a pag.79

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

[...] probably [...] variability of value in the significant compounds of a general linguistic drift [...] is responsible for the rise of dialectic variations. Each dialect continues the general drift of the common parent [...]
- Sapir (1921), a pag.161

[...] if speech sounds exist merely because they are the symbolic carriers of significant concepts [...] why may not a strong drift or a permanent feature in the conceptual sphere exercise a furthering or retarding influence on the phonetic drift?
- Sapir (1921), a pag.184

[...] Tibetan was highly resistant to the polysyllabic words of Sanskrit because they could not automatically fall into significant syllables, as they should have in order to satisfy the Tibetan feeling for form.
- Sapir (1921), a pag.196