THE ARMY OF BLOGGERS came in their thousands. They came to muse, complain, laugh, observe and, above all, to record their lives. They came, at the invitation of the National Trust, to document what happened (or did not happen) to them on October 17, 2006, a single, arbitrary day in the nation’s existence. Some entries were fascinating; the majority were fascinatingly dull. A few bloggers were famous, but most were not. This is autobiography as DIY, all-encompassing CCTV in words.

The One Day in History experiment demonstrated that for all our concerns about educational standards, this is a profoundly literate culture; it proved that the British really do regard tea-drinking as a form of life-punctuation, each cup worth recording for posterity; and it proved that we still believe ordinary life can be spiced up by multiple exclamation marks!!!! But above all this week’s mass blog (from weblog, or online journal) on historymatters.org.uk proved that the personal diary — perhaps the most elemental literary form — is not merely alive, but booming in the internet age as never before.

Anaïs Nin regarded her diary as a form of “opium”, and the fantastic recent efflorescence of blogging shows just how powerfully addictive the personal diary can be. Two years ago, the search term “blog” produced about 150 million results; today, the results exceed 2.5 billion.

This is extraordinary when one considers how debased the diary form has lately become: the waspish jottings of politicians intended to extract revenge and profit when power is gone — Edwina Currie waving John Major’s underwear in print. David Blunkett’s diaries are really a self-justifying memoir with a timeline. A diary deliberately written for publication in the diarist’s lifetime never quite rings true.

The essence of most great diaries, and the best blogs, is not the lure of fame, nor the desire to settle scores, nor even to make money (despite Mae West’s advice: “Keep a diary, and one day it will keep you”). Most diaries spring from the desire to leave an account, however simple and humdrum. The diary-blog is a way of talking to the world, whether or not it is listening; a way of gossiping with oneself in the knowledge or hope that one day someone may eavesdrop or join in.

The diary has always occupied a peculiar niche between the public and the private. Samuel Pepys, the greatest English diarist, wrote his diaries in encrypted shorthand, but left them in bound volumes to his Cambridge college. He wanted them to be read, one day, in all their self-revealing, lewd, joyful enthusiasm. The diary is often a solipsistic and always a solitary occupation, but diaries are also written to be read by some remote audience, even if that audience is only the writer in a later life.

This is what makes the blogosphere so perfectly suited to the diary form. Weblogs are half-published, recording our lives and worries, our hang-ups, relationships and, at excruciating length, the behaviour of our pets. The neurotic mood swings of modern bloggers are not a new phenomenon. On the morning of January 5, 1821, Byron complained to his diary: “Rose late — dull and drooping”, but by the same evening he is back on form: “Clock strikes — going out to make love.” The huge explosion in blogging suggests that so far from being the self- indulgence of a self-obsession generation, the urge to put our individual lives into words may be hard-wired into the human condition.

Francis Kilvert, the 19th-century country parson and diarist, defined the modern blog. “Why do I keep this voluminous journal?” he asked himself. “I can hardly tell. Partly because life appears to me such a curious and wonderful thing that it almost seems a pity that even such a humble and uneventful life as mine should pass altogether away without some such record as this.” The diary-blog is both therapy and exhibitionism, a balm for loneliness, a privately written public statement, a way to hold on to life and to hold back death.

It is no accident that some of the most fertile eras of diary-writing coincide with times of upheaval. Protestant diarists in the age of Pepys may have been responding to a residual Catholic urge to confess. During the First World War, and then the Second, thousands of ordinary people felt moved to record their small lives in the midst of momentous events. Anne Frank wrote to her imaginary friend Kitty as a way to escape and explore her own emotions under the shadow of death.

What is a blog but an uncensored epistle to an imaginary friend? A way to grip and share individual reality, however mundane it may seem at the time? Some of the most fascinating diaries are those written without an awareness of their import. In one tantalising diary entry, Tolstoy wrote: “Quarrelled with Turgenev, and had a wench at my place.”

The blog is the most apt literary form for our lonely, turbulent times: neurotic, self-absorbed, confessional, but also inquisitive, purging and affirming, profound and mundane. The blog can be both opiate and stimulant, but also a placebo.

This week’s mass blog revealed that most of us still measure out the world in cups of tea and telly programmes, but it also proved that, by writing down our experiences, we grow closer to ourselves and leave a testament for posterity. That is a more honest enterprise than any politician’s diary.

By no means all bloggers are Pepys — Pepys never blathers on, as bloggers are prone to do — but Pepys would have been a masterful blogger. Indeed, he is, on www.pepysdiary.com, a daily posting of the diary, which started in 2003 and has just reached Sunday, October 18, 1663.

But it is perhaps Virginia Woolf’s last diary entry that should stand as the bloggers’ motto: “With some pleasure I find that it’s seven; and must cook dinner. Haddock and sausage meat. I think it is true that one gains a certain hold on haddock and sausage by writing them down.”

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