Hobbes's linguistic conventionalism is one of the most obvious themes of his work. But it has not been considered as closely as it should be, given its prominence. I argue that Hobbes reworked quite traditional materials in such a way as to produce a novel doctrine, but that this novelty did not involve him in the implausible claim that issues of scientific truth and proof could be settled simply on the basis of linguistic agreement. Rather, he grounded his conventionalism in the prelinguistic, naturally given experience he called “mental discourse,” and then linked it to the effort to outflank contemporary skepticism. For these reasons, Hobbes's specific form of conventionalism can then be seen to be central both to the limits of his claims and to what he thought could be established with a certainty robust enough to withstand skeptical challenge.

This paper reviews the reliability results for the gallium nitride on silicon (GaN-on-Si) technologies for commercial and military communications markets. Two technology platforms have been qualified for volume production: one consisting of discrete heterostructure field effect transistors (HFETs) and the other consisting of HFETs integrated with passive components to form monolithic microwave integrated circuits (MMICs). The technology platform qualifications for volume production have been achieved through intrinsic reliability tests on the active and passive device elements as well as extrinsic reliability tests at the product level. This paper presents reliability results on accelerated life test (ALT), high temperature operating life under DC and RF stress (DC/RF-HTOL), electrostatic discharge (ESD), ramped voltage breakdown, electromigration, temperature cycling, robustness under voltage standing wave ratio (VSWR) mismatch conditions, and diode stability. Degradation and breakdown mechanisms are discussed in relation to material properties reliability. The results show that the HFET and MMIC technology platforms display reliable performance for 20 year product lifetime at worst case operating conditions.

It is widely agreed that the work of Thomas Hobbes established and continues to nourish the tradition of “realism” in international political theory. But this association is in many ways paradoxical, and above all because Hobbes's avowed purpose was to “show us the highway to peace.” It is usually assumed that he aimed exclusively at internal peace while resigning himself to permanent rivalry among states, but there are a good many indications that this may not be an adequate interpretation. Hobbes devoted substantial effort to explicating several modifications of the inherited intellectual tradition, in both politics and education, that seem to have been intended to promote beneficial effects in interstate relations. When these substantive aims are taken into account, rather different lessons seem to emerge. One, in particular, is that it may be misleading to think of the Hobbesian tradition as one of realism.