[They] loved footnotes. They knew that the outer surface of truth is not smooth, welling and gathering from paragraph to shapely paragraph, but is encrusted with a rough protective bark of citations, quotations marks, italics, and foreign languages, a whole variorum crust of "ibid.'s" and "compare's" and "see's" that are the shield for the pure flow of argument as it lives for a moment in one mind. They knew the anticipatory pleasure of sensing with peripheral vision, as they turned the page, gray silt of further example and qualification waiting in tiny type at the bottom. (They were aware, more generally, of the usefulness of tiny type in enhancing the glee of reading works of obscure scholarship: typographical density forces you to crouch over the busyness and intricacy of recorded truth.) They liked deciding as they read whether they would bother to consult a certain footnote or not, and whether they would read it in context, or read it before the text it hung from, as an hors d'oeuvre.

| Nicholson Baker, The Mezzanine

The experienced reader is conditioned to see footnotes as dry, as a way of grounding the text in reality. But footnotes are also an intervention, or intrusion into the flow of the text... it is in the footnotes that the world of the fantastic slips through to disrupt the meaning or common understanding of the tale told in the main text. The “explanation” they offer is of worlds slipping between each other, of uncontrolled contact with fairy.

| Farah Mendlesohn, Rhetorics of Fantasy