The amount of friendly disagreements about politics is keeping democracy strong in the United States, says a new book co-authored by UC Davis political scientist Robert Huckfeldt.

"You are likely to have three or four people with whom you talk politics, and typically you'll have at least one person in that network who disagrees with you," Huckfeldt said.

His new book, "Political Disagreement," proposes that democracy is alive and well in the United States, with Americans talking among themselves and hearing ideas that conflict with their own political beliefs, Huckfeldt says.

While strongly partisan Americans certainly are less likely to encounter ideas and opinions that are different from their own, Huckfeldt says most Americans have contact with people who differ with them over national politics.

"This is important," Huckfeldt says, "because it means that at least some people are regularly being forced to reconsider their preconceived opinions and beliefs. And these individual reconsiderations lie at the heart of a healthy democratic process."

One effect of having political disagreement among friends is that both parties tend to be less extreme in their positions and less interested in following blow-by-blow accounts of political issues.

Authors Huckfeldt, Paul E. Johnson of the University of Kansas and John Sprague of Washington University interviewed more than 2,000 citizens as well as 1,500 of their associates to find out about people's closest political networks and the degree of disagreement.

"People don't typically choose friends for their politics but rather because they like to hunt, fish, play ball or talk across the fence," Huckfeldt says. "As a result, they like each other and they still have a fair amount of disagreement."