circle" from other groups; and gives a list of "invisible college" members based on this identification. They comprise: William Petty, Boyle, Arnold Boate and Gerard Boate, Cressy Dymock, and Gabriel Platte. Miles Symner may have belonged to this circle. Historiography of the Royal Society Lauren Kassell, writing for the Oxford Dictionary of National Biography, notes that the group of natural philosophers meeting in London from 1645 was identified as the "invisible college" by Thomas Birch, writing in the 18th century; this identification then became orthodox, for example in the first edition Dictionary of National Biography. This other group, later centred on Wadham College, Oxford and John Wilkins, was centrally concerned in the founding of the Royal Society; and Boyle became part of it in the 1650s. It is more properly called "the men of Gresham", from its connection with Gresham College in London. It is the identification of the Gresham group with the "invisible college" that is now generally queried by scholars. Christopher Hill writes that the Gresham group was convened in 1645 by Theodore Haak in Samuel Foster's rooms in Gresham College; and notes Haak's membership of the Hartlib Circle and Comenian connections, while also distinguishing the two groups. Haak is mentioned as convener in an account by John Wallis, who talks about a previous group containing many physicians who then came to Foster's rooms; but Wallis's account is generally seen to be somewhat at variance with the history provided by Thomas Sprat of the Royal Society. Modern use The concept of invisible college was developed in the sociology of science by Diana Crane (1972) building on Derek J. de Solla Price's work on citation networks. It is related to, but significantly different from, other concepts of expert communities, such as Epistemic communities (Haas, 1992) or Community of Practice (Wenger, 1998). Recently, the concept was applied to the global network of communications among scientists by Caroline S. Wagner in The New Invisible College: Science for Development (Brookings 2008). It was also referred to in Clay Shirky's book Cognitive Surplus. In the 1960s, a group of academics (including astronomer J. Allen Hynek and computer scientist Jacques Vallée) held regular discussion meetings about UFOs. Hynek referred to this group as The Invisible College. In fiction, it is mentioned in the novel The Lost Symbol by Dan Brown and Foucault's Pendulum by Umberto Eco. It was the inspiration for the Unseen University