Popular in the seventeenth and eighteenth centuries, a "commonplace book" was a notebook used to gather quotes and excerpts from one's literary wanderings — a kind of personalized encyclopedia of quotations. In "A Letter of Advice to a Young Poet" from 1721, Jonathan Swift remarked that a commonplace book is something that “a provident poet cannot subsist without, for this proverbial reason, that great wits have short memories”. The English physician and philosopher John Locke (1632-1704) was all too aware of the grip of amnesia and the shortness of memory. In his seminal Essay Concerning Human Understanding (1689) he wrote of his rival Blaise Pascal, who he named as the “prodigy of parts”, who “forgot nothing of what he had done, read, or thought.” Locke, in reaction, attempted to simulate Pascal’s "hyperthymesia", not in the mind, but upon the page: through the construction of a system of "commonplacing", as a form of what Swift called “supplemental memory”.