Acetate sheet with sum
Perri MacKenzie, 2011, marker on acetate, 31.5 x 23.3 cm
Recently I attempted to work through a long division problem, live, on an overhead projector in front of an audience. The idea was to demonstrate the two-fold process of “setting up” a situation, then “letting it run,” but in a fit of nerves I forgot the sum I’d taken considerable care to memorize. As the pen squeaked and slipped over the acetate it seemed that the memorized answer and the memorized working-out had fallen out of sync.
Although I knew the result had a repeating decimal 3, I couldn’t manage to contrive its existence. Finally, in confusion and frustration, I just wrote “etc.” and pushed on with the rest of the talk.
Someone later pointed out that this fumbled sum was actually useful in engaging the audience. They were suddenly complicit. It must be difficult, of course, for an audience NOT to automatically follow the process in their heads, or at least try to. Long division, after all, is joyous. But while I’d intended the sum merely to serve as an illustration, it seemed to have become something else altogether. Inviting an audience to participate in a live mental struggle, I realized, creates a strange subjective space.
–“Δ,” Perri MacKenzie, Bulletins of The Serving Library #2, 2011