The online reviews were forthright in their likes and dislikes; the reviewer was anonymous, but displayed a clear interest in Russian history. Robert Service's books were "a dull read", "disappointing" or just plain "rubbish ... an awful book". Rachel Polonsky's Molotov's Magic Lantern, a book universally acclaimed elsewhere, was to this anonymous Amazon reviewer "the sort of book that makes you wonder why it was ever published".

Not that "Historian" was entirely negative in his or her views on books. Orlando Figes's The Whisperers had "superb story-telling skills. I hope he writes for ever". Apart from that, however, Historian was readier to attack than to praise. Moving beyond his or her usual territory of Russian history, Historian wrote of Kate Summerscale's immensely popular and successful The Suspicions of Mr Whicher: "the book is not nearly as good as its many plaudits in the Press and book prize judges think".

Miss Summerscale's book was the good and deserving winner of the Samuel Johnson Prize a year or two back. Curiously, Historian's admired Orlando Figes was also on the shortlist the same year, and failed to win. Even more curiously, this contributor had generated an online profile under the tag "Orlando-Birkbeck", the London college where Mr Figes teaches.

Of course, it must have been immediately apparent to everyone that Orlando Figes himself could not possibly have written these reviews. He himself is rather a good writer, and the reviews, though quick to pass judgement on literary style, were often semi-literate, as that sentence about the plaudits in the Press suggests. Nevertheless, Miss Polonsky was concerned, and Mr Service wrote with his worries to some colleagues. Threatening letters from Mr Figes's lawyers winged out, including to a friend of mine who had commented on events in her Facebook profile.

On Friday the whole thing collapsed. Mr Figes said that he had discovered that the reviews had been written by his wife, Stephanie Palmer, an academic lawyer at Cambridge University. She had abused Mr Figes's rivals and made ecstatically enthusiastic claims for his own works.

With the internet have come huge opportunities for anonymity. Anyone can say what they like about anyone else without there being the slightest risk of an interest, a direct connection, or an obligation being uncovered. That doesn't seem an advantage, on the whole. I can see the reason for SalamPax, the famous gay Iraqi blogger, to write pseudonymously. What possibly justification can there be for a blog of book reviews, or the reviews on Amazon, to remain anonymous, unless to conceal improper interests?

Let's be clear: what Miss Palmer did was an absolute scandal, one to which none of her victims would ever have stooped. When Rachel Polonsky wrote a savagely critical review of a book of Orlando Figes's in 2002, she did so honourably, under her own name in The Times Literary Supplement. Miss Palmer, through her anonymous reviews, has by contrast destroyed all her own credibility, and much of her distinguished husband's. But there is another, larger scandal, which is this. Amazon won't permit you to post a review unless you have ordered books from them. They know your real name. Why do they allow their reviewers to post under pseudonyms anyway? Should not bloggers have to make the case for their anonymity?

Concerts that appeal to the ghoul in me

"Reaction was mixed" and "opinion was divided" usually means not mixed and not divided at all. It usually means everyone thought something was crap. But opinion really is divided about Whitney Houston's amazing concert tour. After a well-documented drug addiction, she is not what she was, and the power and flexibility of her voice have been tragically eroded. Her extraordinary assault on her early 1990s hit "I Will Always Love You" is a current YouTube favourite.

On the other hand, there was genuine adoration in the crowd, along with some booing. Some reviewers – to, admittedly, considerable scepticism – thought that she delivered a compelling show. Probably the two positions are equally true. Audiences have their ghoulish aspect, and sometimes rather hope to see a performer fall apart. One thinks of Judy Garland's legendary run at the Talk of the Town in 1969, where the audience took to throwing breadsticks at the singer.

I freely admit to buying tickets to the appearance of a really past-it diva in an opera with the hope of witnessing an onstage catastrophe. Whitney Houston's gig was nowhere near as bad as that. But her extraordinary charisma just draws the eye, inexplicably, whether what you are looking at is mastery, or something far short of that.

So now we know where the fruit is cut up

Every novelist knows that the introduction of a violent, random event can transform and reveal the truth of a human situation. You don't know what your characters are like until a car crashes into their front garden. Their nature will be revealed by an unpredictable and, in itself, meaningless happening.

And so in real life. No human agency causes the eruption of a volcano, but its remote effects instantly lay bare the rhythms and restrictions of the way we live now. I'm happily ensconced in Geneva, but surprising numbers of friends have been unwillingly stuck in Madrid, Oslo, or much more remote places, dining glumly in hotel restaurants and looking up the train timetables. "Still in Kiev?" I texted a friend who had innocently gone to a conference, never thinking of the effects of an Icelandic volcano on his plans. "For the rest of my life, probably," he replied.

Surely the oddest discovery the Eruption has forced on us is to do with the flying-in of fruit. I bet you didn't know until this week that those little boxes of pineapple chunks come from fruit which have not only been grown in Africa, but peeled, diced and packaged there too. I'm sure this over-elaborate procedure all makes perfect economic sense in normal circumstances. For the immediate future, however, it looks as if you might just have to peel your own fruit.