A reader of the "Paper Spaces" article pointed me to Malcolm Gladwell's 2002 New Yorker essay, "The Social Life of Paper." I read the piece, which is essentially a long essay built around Sellen and Harper's Myth of the Paperless Office, but I didn't realize it was available online.
Gladwell's description of the key affordance of paper– its tangibility, flexibility, and writability (is that a word?)– is particularly nice.
The case for paper is made most eloquently in "The Myth of the Paperless Office" (M.I.T.; $24.95), by two social scientists, Abigail Sellen and Richard Harper. They begin their book with an account of a study they conducted at the International Monetary Fund, in Washington, D.C. Economists at the I.M.F. spend most of their time writing reports on complicated economic questions, work that would seem to be perfectly suited to sitting in front of a computer. Nonetheless, the I.M.F. is awash in paper, and Sellen and Harper wanted to find out why. Their answer is that the business of writing reports — at least at the I.M.F — is an intensely collaborative process, involving the professional judgments and contributions of many people. The economists bring drafts of reports to conference rooms, spread out the relevant pages, and negotiate changes with one other. They go back to their offices and jot down comments in the margin, taking advantage of the freedom offered by the informality of the handwritten note. Then they deliver the annotated draft to the author in person, taking him, page by page, through the suggested changes. At the end of the process, the author spreads out all the pages with comments on his desk and starts to enter them on the computer — moving the pages around as he works, organizing and reorganizing, saving and discarding.
Without paper, this kind of collaborative, iterative work process would be much more difficult. According to Sellen and Harper, paper has a unique set of "affordances" — that is, qualities that permit specific kinds of uses. Paper is tangible: we can pick up a document, flip through it, read little bits here and there, and quickly get a sense of it. (In another study on reading habits, Sellen and Harper observed that in the workplace, people almost never read a document sequentially, from beginning to end, the way they would read a novel.) Paper is spatially flexible, meaning that we can spread it out and arrange it in the way that suits us best. And it's tailorable: we can easily annotate it, and scribble on it as we read, without altering the original text. Digital documents, of course, have their own affordances. They can be easily searched, shared, stored, accessed remotely, and linked to other relevant material. But they lack the affordances that really matter to a group of people working together on a report. Sellen and Harper write:
Because paper is a physical embodiment of information, actions performed in relation to paper are, to a large extent, made visible to one's colleagues. Reviewers sitting around a desk could tell whether a colleague was turning toward or away from a report; whether she was flicking through it or setting it aside. Contrast this with watching someone across a desk looking at a document on a laptop. What are they looking at? Where in the document are they? Are they really reading their e-mail? Knowing these things is important because they help a group coördinate its discussions and reach a shared understanding of what is being discussed.