The conflict thesis, the claim that science and religion have been locked in essentially continuous historical warfare, was given its most influential statements in two nineteenth century works, John William Draper's History of the Conflict Between Religion and Science and Andrew Dickson White's A History of the Warfare of Science with Theology in Christendom, both of which shaped popular understanding of episodes including the Galileo affair for more than a century afterward.
Historians of science specializing in these episodes have since found the conflict thesis considerably oversimplified, and in many specific cases factually wrong: the Galileo affair, the thesis's most cited example, involved specific political, personal and institutional circumstances at least as much as a general religious hostility to heliocentrism, and other frequently cited conflict episodes, including claims about a medieval belief in a flat earth, have been shown by historians to be later inventions with little basis in the actual medieval record. The complexity thesis, now the mainstream position within the history of science as a professional discipline, holds that the historical relationship between religious and scientific institutions and ideas varied enormously by period, place, individual and specific question, sometimes conflictual, often cooperative or simply unconnected, resisting any single overarching narrative in either direction.