Source Negation (Wikipedia)
Source Nicolaas Govert de Bruijn (Wikipedia)
Source Wolfram MathWorld: Nonstandard Analysis
Source Clay Mathematics Institute
Additional Source Wikipedia: P versus NP ProblemLogical characterizations section
Source Wolfram MathWorld: Partial Function
Source Paul Lorenzen (Wikipedia)
Source Wikipedia: Per Lindström
Source Per Martin-Löf (Wikipedia)
Source Petrus Ramus (Wikipedia)
Source Philipp Frank (Wikipedia)
Source Pietro Catena (Wikipedia)
Source Wikipedia: Reuben Goodstein
Source Richard Montague (Wikipedia)
Source Wolfram MathWorld: Richardson's Theorem
Source Robinson's joint consistency theorem, Wikipedia
Source Omega-categorical theory (Wikipedia)
Source Sahlqvist formula (Wikipedia)
Source Sebastián Izquierdo (Wikipedia)
Source Sequent (Wikipedia)
Sets, Concepts Source The Stanford Encyclopedia of Philosophy
Source Absoluteness (logic) (Wikipedia)
Source SKI combinator calculus (Wikipedia)
Source Sofya Yanovskaya (Wikipedia)
Source Soundness (Wikipedia)
Source Stephen Cole Kleene (Wikipedia)
Source Stephen Cook, Faculty Homepage, University of Toronto
Source Tennenbaum's theorem (Wikipedia)
Source Thoralf Skolem (Wikipedia)
Source Turing degree (Wikipedia)
Source Wolfram MathWorld: Turnstile
Source Wolfram MathWorld: Uniqueness Theorem
Source Victor Shestakov (Wikipedia)
Source Vladimir Devidé (Wikipedia)
Source Vladimir Voevodsky (Wikipedia)
Source Walter Pitts (Wikipedia)
Source Wikipedia: Wilhelm Ackermann
Source MacTutor History of Mathematics: Willard Van Orman Quine - MacTutor History of Mathematics
Source William of Ockham (MacTutor)
Showing 101 to 145 of 145 in Includes, page 3 of 3.