Another educational resource which I discovered as well: Dictionary of a History of Ideas.
Studies of Selected Pivotal Ideas, edited by Philip P. Wiener, was published by Charles Scribner's Sons, New York, in 1973-74. . . . The DHI has been out of print for many years. Aware of the new potential offered by electronic access to texts, the Directors and Board of Editors of the Journal of the History of Ideas authorized a grant to support digitization of the DHI. Substantial support has also been provided by the University of Virginia Library through its Electronic Text Center. The project has been undertaken with the permission of Charles Scribner's Sons and of The Gale Group, of which Scribner's is a part.
As if you didn't have enough things to read.