‘I wish you way more than luck.’ I just read David Foster Wallace’s commencement address for the first time, after finding it by accident in the back of an anthology that I only opened because I noticed it was mis-shelved.

A small (though poignant) moment in my reading life, but it points to a crucial fact in the whole paper vs digital book debate: that the books we read have lives before and after the moment of reading, and this is an aspect of the wider reading experience that ebooks have yet to seriously engage with.

You should read, if you haven’t, Tim Parks’ eloquent pro-digital piece in the New York Review of Books ‘E-Books Can’t Burn’. Parks’ central argument is that “Only the sequence of the words must remain inviolate” – that is, when it comes down to it, the experience of literature is all about the act, in the moment, of reading the words on the page. Everything else is extraneous flim-flam or decoration.

I agree, up to a point, and the point is this: that we forget most of what we read, no matter how good or bad it was, and if we want our reading to make a more permanent mark on our consciousness than the pattering of synapses in the particular moment that we have the book in our hands, then we need those words to have some ongoing presence in our lives. We need the lines of communication to be left open.

You might jot down important bits in a notebook, you might tattoo them somewhere on your body, or you might put the book back on the shelf in the hope that, should you need to find it again, you’ll be able to.

Some books you read, and you know you’ll never look at it again. There it goes, happily or unhappily, onto the charity shop pile. Which doesn’t necessarily mean it’s a bad book. Escapism or distraction reading – and all reading involves an element of these things – is as pure an experience, in Parks’ sense, as the deep connection with a piece of fiction that you know, as you read it, will leave your life somehow changed. But unfortunately our brains – or my brain, at least – don’t necessarily hold onto those connections. They slip, they go.

For an e-book to hold that potential mnemonic effect, it would have to have some function whereby you hover over its icon and a bits of text that you’d highlighted, and tags you’d added, float out in a cloud. It’s not just that you’ve got to be able to annotate digital books, but that there’s got to be some subtle, multi-sensory, non-intrusive way for the book to keep reminding you what it holds, or what it holds for you.

This function, in the physical book, is performed by covers, spines, bookmarks, bent pages and post-its, scribbles and exclamation marks, not to mention the things that you can do with the physical book: where you shelve it, how prominently and what next to. Has anyone worked out, for instance, what’s going to become of the ‘downstairs toilet book’ – it would a shame if that genre went extinct just because people don’t keep ereaders in their loos.

The paper books you own are, as I said in a previous post, quoting William Gaddis, the “graphic index of your mind”. And all the trivial, extraneous factors that live in and around the physical book do a real job of work: building up a subtle web of connectivity between the read book (or the unread book) and us, our minds.

Books do more than furnish a room, they work as an external hard drive, a back-up of who we are. The same goes for digital books, obviously, but a ‘desktop’ is not a wall of shelves. They’re not there, nagging away (a very low-key nagging), every day, reminding us of what we’ve read, and who we are.

I’ve called this post A Graphic Index Part II because it links to other posts putting down – very unsystematically – my thoughts about books as objects, print-vs-digital and so on. The others are here:

Put the book back on the shelf: the Graphic Index to your Mind you never knew you had

January reading: Mann, Bolaño, Royle, Griffiths, ‘slow criticism’, the graphic index of your mind Part III

Sally Rooney and the hardback/paperback dilemma (A Graphic Index Part IV)