Native speakers of a language know intuitively whether a sentence is grammatical or not. They usually cannot specify exactly what is wrong, and very possibly they make the same mistakes in their own speech, but they know-unconsciously, not as a set of rules they learned in school-when a sentence is incorrect.

At every moment of his life the Shoshone must be careful to observe the complicated folkways of his group, to do reverence to superhuman powers, to remember the courtesies and obligations of family, to pay homage to certain sacred plants, or to avoid particular places.

Marriage is simply an economic necessity, and so there are no elaborate courtship displays or marriage celebrations among the Eskimo.

Men in all societies possess the biological equipment to remove their hats or shoes, but it is the birth within a particular culture that decides that a Jew will keep his hat and shoes on in his place of worship, a Mohammedan will take off his shoes, and a Christian will keep his shoes on but remove his hat.

The environment does not determine man's culture; it merely sets the outer limits and at the same time offers opportunities.

In place of science, the Eskimo has only magic to bridge the gap between what he can understand and what is not known. Without magic, his life would be one long panic.

The dictionary is a closed system in which someone interested in the meaning of a word can go around and around and end up exactly where he started, simply because words are defined in terms of other words, and these, in turn, are defined in terms of still other words.