[…] our whole mental and moral vocabulary has been gained precisely in this way; the etymologist feels that he has not finished tracing out the history of any one of its terms until he has hunted it back to the physical conception in which, by the general analogies of language, it must have had its origin.
- Whitney (1875), Pag. 89

[…] when science and art and philosophy are making rapid advances, when new branches of knowledge are springing up, one after another, each calling for a whole vocabulary of new terms, when infinite numbers of new facts and new objects are coming to notice, then the native modes of growth, of even the most fertile language, will be taxed beyond their capacity to provide a nomenclature for all. The call is in very great part for technical vocabularies, words for learned use; and the learned find what they want most conveniently in the learned languages.
- Whitney (1875), Pag. 118-119

Every class, however constituted, has its dialectic differences: so, especially, the classes determined by occupation; each trade, calling, profession, department of study, has its technical vocabulary, its words and phrases unintelligible to outsiders […].
- Whitney (1875), Pag. 155

The ordinary vocabulary of the educated, including a great variety of the technical terms of special branches of knowledge with which the educated man must have at least a degree of acquaintance, he may come to understand and to use with intelligence; but there will be whole bodies of English expression which cannot wield, as well as styles to which he does not attain.
- Whitney (1875), Pag. 26

The vocabulary of a rich and long cultivated language like the English may be roughly estimated at about 100,000 words […].
- Whitney (1875), Pag. 26