When people estimate an unknown quantity, their answer is pulled toward any number recently in mind, even one they know is random or irrelevant. Because prices are such estimates, an initial figure sets a reference point that drags subsequent valuations toward it.
Subjects spun a rigged wheel landing on 10 or 65, then estimated the percentage of African nations in the UN. Those who saw 65 gave much higher estimates than those who saw 10, despite the wheel being transparently irrelevant to the question.
People have no stable internal sense of what a thing is worth, yet once an arbitrary starting price is planted, their willingness to pay becomes internally consistent: they will pay proportionally more for more of the item. Preferences are orderly in relation to each other but anchored to a figure with no real basis.
Value is judged relative to a reference point rather than in absolute terms, and the pain of a loss is felt roughly twice as strongly as the pleasure of an equivalent gain. This asymmetry means how an option is framed as a loss or a gain changes which choice people make.
A price looks high or low only relative to the surrounding options a seller presents, not against any objective standard. Introducing a decoy or an extreme high-end item makes adjacent prices seem reasonable, so sellers engineer the choice set to steer judgment.
Because buyers lack a reliable fair-value sense, retailers and menu designers can profitably exploit anchors, charm prices, and context effects to raise what people willingly pay. The book argues real-world pricing is increasingly built on these behavioral findings rather than on classical supply-and-demand rationality.