Milton Erickson was a psychiatrist who had polio twice, was paralyzed and colorblind and tone-deaf, and spent a great deal of his life immobile and observing. He became the most influential hypnotherapist of the twentieth century, and his method was almost the opposite of the popular image of hypnosis.
He did not issue commands. He told stories, digressed, used deliberately vague language, and made suggestions the patient could accept or ignore without ever being aware a suggestion had been made. Bandler and Grinder catalogued the linguistic patterns and called the result the Milton model — described, tellingly, as the inverse of their meta model, which was about making language more precise.
The patterns are worth listing because they are recognizable everywhere once you know them.
Unspecified nouns and verbs: people can change, you may find yourself noticing. Nominalizations, which turn processes into things you cannot examine: your resistance, the healing, our relationship. Mind-reading, in which the speaker asserts the listener's internal state: I know you are wondering. Embedded commands, where an instruction sits inside a larger sentence: you might begin to relax now. Presuppositions of the kind covered in chapter 66. Causal linkage between unrelated items: as you listen to my voice, you will find this makes sense. And the double bind, offering two options that both presuppose the thing being decided.
The mechanism that explains why vagueness is persuasive rather than merely unclear is the generation effect. Slamecka and Graf demonstrated in 1978 that material a person generates themselves is remembered better than material they read, and the broader self-reference literature finds that self-generated content is more persuasive and more resistant to counter-argument. When language is unspecified, the listener must complete it from their own memory to make sense of it — and what they supply is, by construction, personally relevant, emotionally resonant, and already believed.
You cannot argue with a conclusion you produced yourself without arguing with yourself, which is expensive.
The double bind deserves separate attention because it is the most commercially deployed. Would you like to start Tuesday or Thursday. Will you be paying by card or transfer. Shall I put you down for the standard package or the premium. Each offers a real choice at the level of detail and forecloses the question one level up, which is whether to proceed at all. The listener experiences agency — a choice was offered and taken — and the unasked question never surfaces, because answering the asked one feels like having decided.
There is a third mechanism worth noting. Ambiguity increases processing load, and Petty and Cacioppo's work established that counter-arguing requires cognitive capacity. Language that keeps the listener busy constructing meaning leaves less capacity for evaluating it.
The countermeasure for the whole family is a single question, asked out loud, and it is effective out of proportion to its simplicity: what specifically. What specifically do you mean by resistance, by the healing, by people like you. Vagueness cannot survive a demand for specification, because the technique depends entirely on the listener supplying the content. Make the speaker supply it, and either a real claim appears — which you can now evaluate — or nothing does.
Cross-ref: NLP chapter above