“ The consideration, then, of IDEAS and WORDS as the great instruments of knowledge, makes no despicable part of their contemplation who would take a view of human knowledge in the whole extent of it. ”
 John Locke, An Essay Concerning Human Understanding (1689). copy citation

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“And because the scene of ideas that makes one man's thoughts cannot be laid open to the immediate view of another, nor laid up anywhere but in the memory, a no very sure repository: therefore to communicate our thoughts to one another, as well as record them for our own use, signs of our ideas are also necessary: those which men have found most convenient, and therefore generally make use of, are ARTICULATE SOUNDS. The consideration, then, of IDEAS and WORDS as the great instruments of knowledge, makes no despicable part of their contemplation who would take a view of human knowledge in the whole extent of it. And perhaps if they were distinctly weighed, and duly considered, they would afford us another sort of logic and critic, than what we have been hitherto acquainted with.
5. This is the first and most general Division of the Objects of our Understanding.
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