IT IS easy to make fun of the way Donald Trump uses the English language. His tweets tend to follow the same structure: two brief statements, then a single emotive word or phrase and an exclamation mark. (On June 12th, after the Orlando shootings: “We must be smart!”) He invents playground nicknames for his opponents (Little Marco, Lyin’ Ted, Crooked Hillary). His vocabulary is earthy: “big-league”, to describe how he would do things, or “schlonged”, for someone beaten badly. During the primary campaign, his swearing was so criticised that he promised to stop (and actually did).

How did this man become the presidential nominee of the party of Abraham Lincoln? He must be doing something right: after all, language is virtually all a politician has to wield influence with (handshakes and hugs aside). Something about the way he talks and writes swept more experienced politicians aside.

First, he keeps it simple. Journalists sometimes attack politicians for simple language, even going so far as to use a misleading scale used to estimate the difficulty of a reading passage in American schools. These critics say Mr Trump “uses the simple language of a ten-year-old”. But the “Flesch-Kincaid” reading-level test measures only the length of sentences and words, and says nothing about content. At worst, it measures exactly the wrong thing in political speech: short sentences containing common words are, all things being equal, a good thing. “Never use a long word when a short one will do,” Orwell wrote in “Politics and the English Language”. Simplicity is not stupidity; making language easy to apprehend is intrinsic to making it appealing. Countless psychological studies have shown that what is easy to process is seen as more truthful. “I’m going to build a big, beautiful wall and Mexico is going to pay for it” may be preposterous, but it is easy to understand, and the human brain, in its weakness, likes easy things.

Another Trump tactic is repetition. This, too, may be incorrectly seen as childish. Mr Trump does often say exactly the same thing several times in a row in a crude, hammer-blow fashion. But in more sophisticated guise, repetition is a venerable rhetorical tool. Mark Antony sarcastically repeats the taunt that Brutus is “an honourable man” after Brutus murders Caesar. Winston Churchill rallied Britain with, “We shall fight on the beaches, we shall fight on the landing grounds, we shall fight in the fields and in the streets…” And the most beloved rhetorical repetition of the 20th century is the great refrain, “I have a dream.” Mr Trump is certainly no Martin Luther King, but he knows how to leave an audience remembering what he said.

Yet the most effective way Mr Trump beguiles his audience is perhaps the simplest: he does not give speeches. Instead, he talks. (Only rarely, when even he realises that his mouth can get him into trouble—as in his first speech after the Orlando shootings—does he resort to a teleprompter.) He does not even seem to have a “stump speech”. Bored reporters following ordinary candidates on the trail know that, even though they speak without notes, politicians reheat the same hash in town after town. Mr Trump, as noted above, repeats many tropes. But he also genuinely speaks off the cuff, avoiding the standard sunny string of clichés, which makes him fascinating to journalists. A Trump speech may actually make news. This is what happened when a barely planned digression about a fraud case generated a controversy: Mr Trump rambled that the judge ruling against him was conflicted because he was “a Mexican” (actually an American-born son of Mexican parents).

This unscripted quality is powerful. Even a valid argument is weakened if it sounds canned. Even an invalid one sounds stronger if it appears spontaneous, especially to voters disgusted with the professional politicians. This reveals a dangerous double edge to Orwell’s famous rules for clear and honest English. An honest speaker would do well to keep words and sentences short and concrete, and to avoid clichés, as Orwell advises. But a demagogue can use these tools, too. Orwell believed in the talismanic power of clear language to make lies and appalling talk plain. But some voters cannot recognise a lie, and others want to hear appalling things. If there are enough of these, then a looseness with the facts, a smash-mouth approach to opponents and a mesmerisingly demotic style make a dangerously effective cocktail.