How we change what others think, feel, believe and do
Agree and Extend
First get their agreement, then assumptively extend that agreement.
This can be done over time, within the same conversation, and even within the same sentence.
The basic principle is to make a statement to which the other person will readily agree, then to add more items and act as if they also agree to this.
A simple way to do this is in the same sentence, to briefly pause after the first statement to let them say yes, then continue with the rider on which you really want agreement. It may help to carry on talking for a while to prevent them from challenging your assumption.
Another way, in a longer conversation, you might first get agreement to such as a general request for help before getting into the specifics of exactly what help you want.
Over time, you could engage them in something, then steadily extend the
activity into areas they might not have originally accepted.
Do you like the shirt? (Yes) Then you'll love this tie which is designed specifically to go with it.
Can we go to town? (Yes) While we're there, let's visit my mother.
Assumptive methods work by acting 'as if' something is true and then making it difficult or embarrassing to contradict this. Agree and Extend strengthens this by priming the person with the easy agreement.
When a person has agreed to something, they switch to a state of comfortable closure. An additional request threatens to drag them out of that comfort with a new tension, so they may well quickly and unthinkingly agree again in order to switch back to the closure comfort.
There is also a sunk cost effect, where having agreed, the subject feels they have made a significant investment and to subsequently pull out would result in the loss of that commitment. So they stay in and become trapped by ever increasing investment. This is strengthened again by the fear of embarrassment should they be shown as having made a bad decision.
Agree and Extend works more easily if the extension is a small step, though if the person is in a good mood or has relaxed after the closure.
And the big