I find the notion of distributed cognition compelling - that our thinking is not just something that happens in our heads but that is distributed in the world and the people around us is pretty obvious and a host of people have come up with different theories and models to express that - apart from the distributed cognition field itself, social and otherwise, this concept underlies actor network theory, activity theory and a great many less formal models. I came across it again the other day in Steven Johnson's great new book, Future Perfect, where he talks about the successful landing of a plane hit by geese as 'a kind of duet between a single human being at the helm of the aircraft and the embedded knowledge of the thousands of human beings that had collaborated over the years to build the Airbus A320's fly-by-wire technology'. I like the 'duet' metaphor but the concept also relates to how we organize our own lives and the objects we surround ourselves with.

I am writing a book at the moment that requires me to synthesize and integrate a great many ideas that I have picked up from many places. When I am at a loss about where to go next, I tend to glance at my bookshelf, where the familiar volumes remind me of what I have not connected and not included, often sparking a cascade of ideas. Unfortunately, I have purchased very few physical books over the past two years or so, since getting my first iPad. This means that I must make an active effort to skim through the icons of the books on the device to remind myself of what I know. Sure, there are compelling advantages to the e-books like size, ease of reading, much easier searching, indexing and aggregation, not to mention their availability on multiple devices, but I have to know what I am looking for. Also, the icons of individual books are just too similar - I recognize physical books by their size, shape, dog-eared covers and so on. A similar thing has happened with music. CDs are way less recognizable than albums, and tunes on an iPod blend into a blur of sameness when viewed on the tiny screen, album images notwithstanding.

The same is true for skimming through books once I have picked them from the shelf - I recognize important places and remember things about them by their context in relation to other words in the book, the shapes of paragraphs, the flaws on the page, my annotations, etc. I have written elsewhere of ideas for improving electronic books to restore some of that context  by embedding small variations in the fonts based on a hash of nearby words or showing subtle watermarks that adapt with the text around them, and I wish someone would build that: it would make e-books more memorable and useful.

However, for those physical reminders of my thinking history, I want something more. It's great having it all on a device the size of much less than one of those books (at least on the Nexus 7 I increasingly prefer to the iPad) but sometimes it would be nice to spread it out a bit more, to surround myself with books in some physical form. I wonder if there is a market for virtual bookshelves. By this, I mean a display device of the size and dimensions of a bookshelf on which one could place virtual artefacts, perhaps even made to look like the books that they represent. You could take a book 'out' by maybe touching it, possible with the device on which you want to read it (using NFC). Unlike a real bookshelf you could also very easily reorganize your shelf in different orders, zoom bits of it, filter it. This idea is extensible - music could be accessed the same way, or academic papers, or movies, or notes (like sticky notes). All of this is possible and available on the small screen but size matters here. Even the biggest of current TV screens cannot come close to replicating the diversity and quantity of things that I would like to have to hand (or to eye) and, even if they were big enough, I'm not sure I'd appreciate the glow of such a device filling a wall-sized space. It could be done with a projector, perhaps, maybe linked with a Kinnect-like device to make it easy to interact with, but shadows would be a major problem. E-ink/e-paper would do the job: no unwanted glow, almost zero power consumption, and the slow refresh rate would be no problem at all. But does anyone make e-ink displays several metres across? 

In the meantime, one answer to by current problem would be, when reading or writing something, to display relevant digital objects (books, papers, etc) that are selected based on keywords of what you are reading or writing, perhaps showing them on a separate display screen. Something primitive like that is happening right now as I write this, as I see my tag cloud from my former blog posts next to this blog form. Yes, it would potentially distract, and care would be needed to avoid too rapid or too slow change in the list displayed. But it could easily be turned off.