Paradoxes, such as the Liar (‘What I am saying is false’), fascinated medieval thinkers. What I said can’t be true, for if it were, it would be false. So it must be false—but then it would be true after all. Attempts at a solution to this contradiction led such thinkers to develop their theories of meaning, reference and truth. A popular response, until it was attacked at length by Thomas Bradwardine in the early 1320s, was to dismiss such self-reference as impossible: no term (here, ‘false’) could refer to (or in medieval terms, “supposit for”) a whole, e.g., a proposition, of which it is part. In light of Bradwardine’s criticisms, Walter Segrave, writing around 1330, defended so-called restrictivism (restrictio) by claiming that such paradoxes exhibited a fallacy of accident. The classic example of this fallacy, the first of Aristotle’s fallacies independent of language, is the Hidden Man puzzle: you know Coriscus, Coriscus is the one approaching, but you don’t know the one approaching since, e.g., he is wearing a mask. But Aristotle’s account is unclear and Segrave, building on ideas of Giles of Rome and Walter Burley, shows how the fallacy turns on an equivocation over the supposition of the middle term or one of the extremes in a syllogism. Thereby, Segrave is able to counter Bradwardine’s arguments one by one and defend the restrictivist solution. In this volume, Segrave’s text is edited from the three extant manuscripts, is translated into English, and is preceded by a substantial Introduction.

2 Peter of Aillyl wrote his Concepts and Insolubles, according to the best 3 estimate, in 1372. He was at that time only about twenty-two years old. He was born around 1350" in Compiegne in the De de France, although his 5 family name associates him with the village of Ailly in Picardy. In 1364 he entered the University of Paris as a 'bursar' (i. e. , the recipient of a scholarship) at the College de Navarre. He received the degree of Bachelor of Arts in 1367 and taught there until 1368, when he entered the Faculty of Theology. He became a Doctor of Theology in 1381. In the years that followed, Peter was very active in the 'conciliar' movement and in negotiations to bring about the end of the Great Schism of the West. He was elevated to the rank of Cardinal in 1411 by Pope John XXIII, the successor of Alexander V in the 'Pisa' line of Popes. He took an active part in the Council of Constance (1414-1418), which ended the Great Schism and elected Pope Martin V. Peter died on August 9, 1420. Most of the secondary literature on Peter of Ailly concerns his role in church politics, his writings on the Schism and on ecclesiastical reform, and various aspects of his theology. But Peter was active in a number of other areas as well. He wrote several works, for instance, on geography and astron 6 omy, including an Imago mundi read by Christopher Columbus.

In support of the U.S. Dept. of Energy (DOE) Fuels Technologies Program Multiyear Program Plan Goal of identifying fuels that can displace 5% of petroleum diesel by 2010, the Nat. Renewable Energy Lab. (NREL), in collaboration with the Nat. Biodiesel Board (NBB) and with subcontractor Southwest Research Institute, performed a study of biodiesel oxidation stability. The objective of this work was to develop a database to support specific proposals for a stability test and specification for biodiesel and biodiesel blends. B100 samples from 19 biodiesel producers were obtained during Dec. 2005 and Jan. 2006 and tested for stability. Eight of these samples were then selected for additional study, including long-term storage tests and blending at 5% and 20% with a number of ultra-low sulfur diesel (ULSD) fuels. These blends were also tested for stability. The study employed accelerated tests as well as tests intended to simulate three real-world aging scenarios: (1) storage and handling, (2) vehicle fuel tank, and (3) high-temperature engine fuel system. Results were analyzed to determine whether ensuring B100 stability was adequate to ensure the stability of B5 and B20 blends. Several tests were also performed with two commercial antioxidant additives to determine whether these additives might improve stability. This report documents completion of the NREL Fiscal Year 2007 Annual Operating Plan Milestone 10.1. Illus.