Scholars have not examined public views of scientific motivations directly, despite scientific authority implications. A US representative sample rated 11 motivations both descriptively (they do motivate scientists’ work) and normatively (they should motivate scientists) for scientists employed by federal government agency, large business corporation, advocacy group (nonprofit seeking to influence policy), or university. Descriptive and normative ratings fell into extrinsic (money, fame, power, being liked, helping employer) and intrinsic (do good science, enjoy challenge, helping society and others) motivation factors; being independent and gaining respect were outliers. People saw intrinsic motivations as more common, but wanted intrinsic motivations to dominate extrinsic ones even more. Despite a few differences for extrinsic-motivation ratings, the lay public tended to see scientific work as similarly motivated regardless of the employer. Variance in perceived science motivations was explained by scientific beliefs (positivism, credibility) and knowledge (of facts and scientific reasoning), complemented by political ideology and religiosity.