Overwhelming majorities of Americans believe that science has had a positive impact on society and that science has made life easier for most people, but Americans don't think as highly of American science as do scientists. Those are the among the results from a survey released Thursday by the Pew Research Center for the People and the Press, and the American Association for the Advancement of Science. Only 17 percent of Americans believe that their country's scientific achievements rate as the best in the world, compared with nearly half (49 percent) of scientists who hold that view.