Priority becomes a difficult issue usually in the context of priority disputes, where the priority for a given theory, understanding, or discovery comes into question. In most cases historians of science disdain retrospective priority disputes as enterprises which generally lack understanding about the nature of scientific change and usually involve gross misreadings of the past to support the idea of a long-lost priority claim. Historian and biologist Stephen Jay Gould once remarked that "debates about the priority of ideas are usually among the most misdirected in the history of science."[3]