This quarter I’m requiring the students in my eighteenth-century literature class to maintain a commonplace book. A commonplace book is a book into which you copy passages from your reading that you would like to keep on hand for reference, passages that are striking for their insight, their style, their beauty, their humor, or their embodiment of something significant.

Our system of commonplacing is based on a 1799 “improvement” to John Locke‘s method for indexing a commonplace book. As this 1799 text reads,

The man who reads, and neglects to note down the essence of what he has read; the man or woman who sees, and omits to record what he has seen; the man who thinks, and fails to treasure up his thoughts in some place, where may readily find them for use at any future period; will often have occasion to regret an omission, which such a book, as is now offered to him, is calculated to remedy.

John Locke’s “new method of making common-place books” sought “to increase the amount of information one could annotate in the notebook, while also speeding up its retrieval,” by creating a system of indexing the book’s quotations. He proposed that each topic to be included in the commonplace book be represented by a keyword that is then reduced to a two-letter code. These two letters were the first letter of the word followed by the first vowel. The word, “Passion,” for example, would be represented by the code “Pa;” the word, “Order,” would be represented by the code “Oe;” and the word, “Art,” would be represented by the code “Aa,” since it has only one vowel. Entries in the commonplace book would be indexed according to these codes.

Whenever he found a passage that he wanted to include in his notebook, Locke would assign it a keyword (and thus a code). He would write the keyword at the top of a page. He would then reserve that page for entries on that topic. When he had a passage with a different key word that he wanted to record, he would go to the next free page, write the word at the top, and then transcribe the passage.

If Locke wanted to write down the following quotation from Richard Hooker:

Happiness is that estate whereby we attain, so far as possibly may be attained, the full possession of that which simply for itself is to be desired, and containeth in it after an eminent sort of the contentation of our desires, the highest degree of all our perfection.

He would open his commonplace book to the first clear page (assuming he hadn’t already started a section on “happiness”). Imagining that the first available page was page 16, for example, Locke would write “Happiness” at the top of the page and transcribe the quotation. Next, he would turn to the index, find the section of the index grid for “Ha,” and record the number 16 there.