A recent generation of historians of science, far from portraying accepted scientific views as objectively accurate reflections of a natural world, explain the acceptance of such views in terms of the ideological biases of certain influential scientists or the institutional and rhetorical power such scientists wield. As an example of ideological bias, it has been argued that Pasteur rejected the theory of spontaneous generation not because of experimental evidence but because he rejected the materialist ideology implicit in that doctrine. These historians seem to find allies in certain philosophers of science who argue that scientific views are not imposed by reality but are free inventions of creative minds, and that scientific claims are never more than brave conjectures, always subject to inevitable future falsification. While these philosophers of science themselves would not be likely to have much truck with the recent historians, it is an easy step from their views to the extremism of the historians. While this rejection of the traditional belief that scientific views are objective reflections of the world may be fashionable, it is deeply implausible. We now know, for example, that water is made of hydrogen and oxygen and that parents each contribute one-half of their children's complement of genes. I do not believe any serious-minded and informed person can claim that these statements are not factual descriptions of the world or that they will inevitably be falsified. However, science's accumulation of lasting truths about the world is not by any means a straightforward matter. We certainly need to get beyond the naive view that the truth will automatically reveal itself to any scientist who looks in the right direction; most often, in fact, a whole series of prior discoveries is needed to tease reality's truths from experiment and observation. And the philosophers of science mentioned above are quite right to argue that new scientific ideas often correct old ones by indicating errors and imprecision. Nor would I deny that there are interesting questions to be answered about the social processes in which scientific activity is embedded. The persuasive processes by which particular scientific groups establish their experimental results as authoritative are themselves social activities and can be rewardingly studied as such. Indeed, much of the new work in the history of science has been extremely revealing about the institutional interactions and rhetorical devices that help determine whose results achieve prominence. But one can accept all this without accepting the thesis that natural reality never plays any part at all in determining what scientists believe. What the new historians ought to be showing us is how those doctrines that do in fact fit reality work their way through the complex social processes of scientific activity to eventually receive general scientific acceptance.