By VERLYN KLINKENBORG
New York Times, Nov 12, 2003
o you know what an exabyte is? I didn't until I started reading a new report, called "How Much Information? 2003," from the University of California at Berkeley's School of Information Management and Systems. An exabyte turns out to be a billion gigabytes. Most new computers, by comparison, come with hard drives around 40 to 100 gigabytes in size.
The authors of the report estimate that in 2002 the human species stored about five exabytes of new information on paper, film, optical or magnetic media, a number that doubled in the past three years. Five exabytes, as it happens, is equivalent to all words ever spoken by humans since the dawn of time.
To gauge how much new information humans now produce in a given year, you have to imagine digitizing and storing all of it, including forms of information that aren't already digital and forms that aren't usually stored, including all e-mail messages, all the Web pages on the entire Internet and all telephone conversations.
As the authors point out, "The striking finding here is that most of the total volume of new information flows is derived from the volume of voice telephone traffic, most of which is unique content." In 2002, that telephone traffic added up to about 17 exabytes, more than three times all the words ever spoken by humans until that point.
Staring at numbers and comparisons like this, which are more than merely boggling, is enough to make you wonder just what information is. Perhaps it seems obvious to say that information of the kind that can be stored and counted up is created and consumed entirely by humans. So let me say it another way. Our idea of information is meaningless to the rest of creation. The cocoon of data and language that humans live in goes undetected by the rest of earth's organisms. In all those exabytes of chatter there are words, of course, that refer to something beyond the narrow bounds of human experience. But vast quantities of what gets cataloged as information are purely self-referential, talk about the act of talking, so to speak. That is partly what makes us human.
I find myself wondering about other kinds of information. The precise pattern in which the autumn leaves lie in my pasture would not be "information," according to the analysts at Berkeley, unless I took a photograph of it, preferably a digital one. But even without the photograph, the pattern is information, shifting momentarily under a cold, bright wind out of the west. If you were to ask how much information the earth contains, as a whole, one way to answer the question would be to assess the number of bytes present in all the DNA on earth, once it had been digitized. But that is too static an answer for me. It treats each being as a museum specimen, ready to be closed away in a dark drawer somewhere, and it rules out the possibility that movement itself and the interaction of all these beings is also information. If it's somehow plausible to treat all the interrupted cellphone conversations in 2002 as a kind of information, then it should be plausible to think of all the bird songs and insect noises uttered in that calendar year as information, too.
It's worth pointing out that "information," in the Berkeley sense, is a wholly biological enterprise on our part — not that different, in a way, from the webs that spiders build. But after reading the report all I could hear in its pages was the silence of the rest of nature, nature's lack of "information," its inability to yield storable data.
Yet that is not my experience. I spend part of every week wired to the world, with an intravenous connection to the Internet. I read and talk and listen. And yet even in my office I am inundated with what cannot be calibrated. The body language I witness when a politician stops by is information to me, but not "information." The unsettled emotions I experience as I read through my stack of newspapers every day is information, too, but not "information."
And when at last I go home to the country, I step out of the pickup truck and into a world of pure information, all of it entirely, gloriously ephemeral. The moon is low in the southern sky. The ducks, disturbed by my headlights, stir in their pen and make delicate, reassuring noises. The bare tree branches cross and cross again against the stars on the horizon. One of the pigs rolls over in his house, and I can hear the weight of his body as he settles into his hay. These observations are now "information," but what they are to me cannot be measured.