Ever since David Hume noted that, while reading Edward Gibbon’s The History of the Rise and Fall of the Roman Empire, “One is also plagued with his Notes, according to the present Method of printing the Book” and suggested that they “only to be printed at the Margin or the Bottom of the Page,” footnotes have been the hallmark of academia. For centuries, then, the footnote existed as a blunt instrument, wielded by pedants and populists alike, primarily for the transmission of information, but occasionally to antagonize opponents with arch rhetorical asides. But it would take a couple hundred years until writers again took up the footnote for other, more artful purposes, discovering in this tiny technique emotional and intellectual depth far beyond the realm of the merely experimental.  

Source: On the Fine Art of the Footnote ‹ Literary Hub