The Internet, above all, is about communication. What we’re able to say online, how we should say it, and how other people say it are among the more fascinating aspects of the digital world.

The U.S. Supreme Court recently made groundbreaking news in this area, news that not everyone is pleased with. It just overturned a lower court decision that had supported a prison sentence given to a Pennsylvania man who posted messages on Facebook about killing his estranged wife.

The man’s defense was that he wasn’t serious and that his posts were akin to rap music lyrics. The Supreme Court overturned the lower court’s decision and a previous jury verdict and sided with the man, with seven justices voting to throw out the conviction, one voting to support it, and one voting to return the case to an appeals court.

The man’s words were ugly. In one post about his wife he wrote, “There’s one way to love you but a thousand ways to kill you. I’m not going to rest until your body is a mess, soaked in blood and dying from all the little cuts.”

The man’s lawyers argued that his posts were a spontaneous form of expression that shouldn’t be considered threatening because he didn’t really mean it and that they should receive protection under the First Amendment.

To the chagrin of women’s and victim’s rights groups, the Supreme Court agreed. It held that the man couldn’t be convicted merely on the basis of the words, even if a reasonable person might consider them threatening. The court ruled that the man could be prosecuted only if he actually intended his words as threats.

The National Center for Victims of Crime contends that it will now be more difficult to persecute stalking crimes.

The man, Anthony Elonis of Bethlehem, Pa., used the pseudonym “Tone Dougie” in his posts, rather than his real name. He’s currently in jail in Pennsylvania on unrelated assault charges after throwing a pot at a woman.

Most of us have seen people lose control on Facebook and Twitter, on blogs and in discussion groups, in emails and in texts, letting loose with angry rants, name calling, cursing, threats, or attacks on another person’s motivations, competence, lifestyle, or national, racial, or religious background.

The name for this type of activity is “flaming,” and such words are called “flames.” The Internet makes flaming more common than in other forms of discourse. You’re separated from others by space and often by time as well.

But abusive discourse isn’t unique to the Internet. Writers, who you might think would know better, are infamous for letting loose:

• Mark Twain on Jane Austen: “Every time I read Pride and Prejudice, I want to dig her up and hit her over the skull with her own shin-bone.”

• H.G. Wells on George Bernard Shaw: “An idiot child screaming in a hospital.”

• D.H. Lawrence on Herman Melville: “Nobody can be more clownish, more clumsy and sententiously in bad taste, than Herman Melville.”

• Gustave Flaubert on George Sand: “A great cow full of ink.”

• Gore Vidal on Truman Capote: “He’s a full-fledged housewife from Kansas with all the prejudices.”

• Friedrich Nietzsche on Dante: “A hyena who wrote poetry on tombs.”

• Oscar Wilde on Alexander Pope: “There are two ways of disliking poetry; one way is to dislike it, the other is to read Pope.”

• Gertrude Stein on Ezra Pound: “A village explainer. Excellent if you were a village, but if you were not, not.”

• Charles Baudelaire on Voltaire: “I grow bored in France—and the main reason is that everybody here resembles Voltaire … the king of nincompoops, the prince of the superficial, the anti-artist.”

• Dylan Thomas on William Wordsworth: “Wordsworth was a tea-time bore, the great Frost of literature, the verbose, the humourless, the platitudinary reporter of Nature in her dullest moods.”

• Evelyn Waugh on Marcel Proust: “I am reading Proust for the first time. Very poor stuff. I think he was mentally defective.”

• Raymond Chandler on James M. Cain: “Everything he touches smells like a billygoat. He is every kind of writer I detest, a faux naif, a Proust in greasy overalls.”