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Most recent writers of informal logic texts draw a distinction between "linked" and "convergent" arguments. According to its inventor, Stephen Thomas, the distinction is of the utmost importance; it "seems crucial to the analysis and evaluation of reasoning in natural language." I argue that the distinction has not been drawn in any way that makes it both clear and of any real originality or importance. Many formulations are obscure or conceptually incoherent. One formulation of the distinction does seem tolerably clear and I develop another, but neither promises to make it matter much. We can well do without it.

Is capitalism inimical to community? Yes, say communitarians, a large part of whose body of writing is given over to the elaboration and defense of various forms of this thesis. The aim of the present essay is to contest this answer. Not only, I will argue, is there no good reason for supposing capitalism inimical to community, but there is reason to think it more conducive to community than are the feasible alternatives to it.

MIT Lincoln Laboratory (MIT LL), in an effort sponsored by the National Center of Atmospheric Research (NCAR), has engaged in the development of C-Band active element phased array front-end hardware for a polarimetric radar application. This polarimetric active element scanning array (AESA) radar, when fully developed, would be deployed on a C-130 for use in Hurricane Hunter-like missions. The combination of mission and platform imposes requirements on the RF hardware that are often in conflict. These specifications include minimum range and resolution, maximum prime power, and a challenging cross-polarization isolation requirement. The RF hardware developed included a dual polarization (pol) radiator test panel, an alternating transmit simultaneous receive (ATSR) transmit/receive (T/R) switch designed and manufactured by M/A-COM Technical Solutions (MTS), a three channel T/R multichip module (MCM), and a four-pack T/R module assembly. This paper describes the mission and platform requirements, presents a notional design for the phased array aperture, discusses the design trades, and provides an overview of the design and performance of the radiator test panel, the MCM and the four-pack T/R module. This work borrowedheavily in terms of materials, technologies, and lessons learned acquired over the past five years from the MPAR Panel [1] development efforts of MIT LL and MTS co-sponsored by the Federal Aviation Administration (FAA), the Air Force, and the National Severe Storms Laboratory.