From the point of view of language, thought may be defined as the highest latent ot potential content of speech, the content that is obtained by interpreting each of the elements in the flow of language as possessed of its very fullest conceptual value.
- Sapir (1921), a pag.14

[...] thought may be no more conceivable, in its genesis and daily practice, without speech than is mathematical reasoning practicable without the level of an appropriate mathematical symbolism [...]
- Sapir (1921), a pag.15

Thought may be a natural domain apart from the artificial one of speech, but speech would seem to be the only road we know of that leads to it.
- Sapir (1921), a pag.15

[...] the most rarefied thought may be but the conscious counterpart of an unconscious linguistic symbolism.
- Sapir (1921), a pag.16