If you’re trying to win over people who may not agree with all (or even many) of your premises.
For instance, here’s one posted a few days ago on National Review Institute’s Media Malpractice blog:
The number of Americans who are poor, sick, and uninsured for a lengthy
period is a relatively small number, about 4 million individuals.
Puts the argument for a massive government takeover of the medical system in a different light. Or it should.