The proof theory of classical and constructive inductive definitions. A 40 year saga, 1968-2008.
نویسندگان
چکیده
1. Pohlers and The Problem. I first met Wolfram Pohlers at a workshop on proof theory organized by Walter Felscher that was held in Tübingen in early April, 1973. Among others at that workshop relevant to the work surveyed here were Kurt Schütte, Wolfram’s teacher in Munich, and Wolfram’s fellow student Wilfried Buchholz. This is not meant to slight in the least the many other fine logicians who participated there. In Tübingen I gave a couple of survey lectures on results and problems in proof theory that had been occupying much of my attention during the previous decade. The following was the central problem that I emphasized there:
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