‘Going to Extremes’

Obama regulatory czar Cass Sunstein's new book analyzes how polemical thinking feeds on itself: when we're with like-minded people, soft views harden, and we begin to resist challenges to our ideas. The best bits:

In 2005, Sunstein asked liberals and conservatives to write down their views on social issues (gay unions, climate change). Subjects were then split into like-minded groups for 15 minutes. Almost all became more dogmatic in their views. This is called "group polarization."

Terrorist networks thrive on group polarization. The surest way to build an extremist group, or a cult, is to separate its members from society by cultivating a sense of suspicion about nonmembers.

In the 1971 "Stanford Prison Experiment," students played "prisoners" and "guards" in a mock jail on campus. Some guards terrorized inmates, and appeals to their reason often backfired, demonstrating a tendency to become more entrenched when challenged, not less.

The Web unites—and it polarizes. Online, it's possible to filter news into what Sunstein calls the "Daily Me": a flow of information that only reinforces one's previously held opinions.