After all, this is the planet's forests being transformed into thermal insulation and room decoration at the rate of about 250 million tonnes a year. Is this really the right thing to be doing?

No doubt about it, paper is a nice medium, and very convenient with zero boot-up time, no batteries and the capacity to be folded into a shirt pocket. Relatively speaking paper is also very low-cost as we have become very efficient in its manufacture and reprocessing. In this equation we should not dismiss our individual years of dedication to learning to read and write efficiently. The cost of this skill acquisition is unlikely to be overtaken by the average lifetime of paper consumption we could anticipate enjoying. Perhaps surprisingly, the cost of providing a computer screen for life falls into the same bracket as the cost of paper we each consume. This means we are becoming extraordinarily efficient, as working on screen gives at least a tenfold gain over paper-based systems.

Although in my work I avoid paper like the plague, and make every effort to avoid printing anything, I still enjoy the look and feel of the occasional book. For non-technical works I am happy to buy a paper or hardback and read in my armchair, but textbooks present a problem. I can never find one book that covers my topic of study and is not deficient in one regard or another. What I need is the ability to cook my own. A chapter from here, a paragraph from there and figures and diagrams from another. Come to think about it, I'd like to do this with music CDs and tapes too. They never have my choice or optimum selection, and cannot be updated and augmented.

Even with no power of content selection and format cooking, I like music stores that let me sample their products before I buy. The old libraries and bookstores were fun too: I used to enjoy being able to browse, sample and choose. But now I would like one more degree of freedom; to download and try on my screen, to modify, add to and compile my own volumes, and then if I really need to, print.

Consider the efficiency (the ratio of in-hand to on-shelf time) of any book you buy - it is hard to exceed 0.02 per cent for a novel and 0.2 per cent for a textbook. Just think how many times you read your individual books, and how many hours they are in your hands during their lifetimes. In contrast, and given the ultra-low cost of digital storage, the efficiency of information retention and use on a PC (replaced every three years) is likely to exceed 10 per cent. I estimate my own information storage efficiency to be around 15 per cent. I suspect that if you get past 30 per cent you make some dramatic transition into a new class of human.

As I type these 600 words I am sitting in a forest surrounded by unbounded beauty, trees of all kinds. What are we doing, reducing them to pulp just to record our words for a few decades, and give them the attention of or eyes for an hour or two? I feel kind of comfortable here - among friends.

Peter Cochrane holds the Collier Chair for the Public Understanding of Science & Technology at the University of Bristol. His home page is:
http://cochrane.org.uk