Why do some arguments fail to persuade, even when the evidence seems overwhelming?
Philosopher Stephen Toulmin offered an answer: every argument rests on a warrant, the often unspoken principle that links the evidence to the conclusion. Reject the warrant and the evidence loses its power.
In my latest article, I explore the power of warrants and their implications for persuasion. Drawing on a landmark study of public attitudes to genetic research, I show how warrants are shaped not just by science, but by personal experience, history, culture and even fiction.
I then look at three domains where warrants make or break persuasion: politics (gun control), public health (vaccination), and marketing (Jobs to Be Done theory).
The lesson is clear: persuasion is not just about piling up data but also about recognising and working with the warrants your audience already holds.