The ArgumentHistorians of science naturally tend to express interest in other forms of intellectual activity only when these intersect with science. This tendncy has produced a number of enlightening studies of what happens when science and (for instance) law or theology come into contact, but little by way of how science enters into the calculations and social status of such forms of knowledge after the conjuction has passed. Recent work in the sociology of professions, in contrast, has focused attention precisely (...) on those moments when the expert knowledge produced by different group doesnotoverlap. This has been the contribution of Andrew Abbortt's theory of “jurisdictional boundaries” between competing professions. The case of Victorian actuaries who worked hard to maintain unique intellectual claims in the competitive life insurance industry while maintainiing strong social connections and overlaps in knowledge with organized science, challenges the way both historians of science and sociologists of professions view contending knowledge claims. By observing what motivated actuaries to forge an alliance with men of science in the 1820s, then tracing their gradual recognition of a need to distance themselves from certain of the “scientific” values that had earlier informed their collective identity, it is possible to make sense of connections as well as disconnections between science and other forms of knowledge. A history of quantification from the actuaries' perspective, in other words, allows us to view science bothasandincontext. (shrink)