Predicate Calculus - National Taiwan University
... Example 2: S={P(x)∨Q(x),R(z),T(y)∨∼W(y)} There is no constant in S, so we let H0={a} There is no function symbol in S, hence H=H0=H1=…={a} Example 3: S={P(f(x),a,g(y),b)} H0={a,b} H1={a,b,f(a),f(b),g(a),g(b)} H2={a,b,f(a),f(b),g(a),g(b),f(f(a)),f(f(b)),f(g(a)),f(g (b)),g(f(a)),g(f(b)),g(g( ...
... Example 2: S={P(x)∨Q(x),R(z),T(y)∨∼W(y)} There is no constant in S, so we let H0={a} There is no function symbol in S, hence H=H0=H1=…={a} Example 3: S={P(f(x),a,g(y),b)} H0={a,b} H1={a,b,f(a),f(b),g(a),g(b)} H2={a,b,f(a),f(b),g(a),g(b),f(f(a)),f(f(b)),f(g(a)),f(g (b)),g(f(a)),g(f(b)),g(g( ...
compactness slides
... The language of sentential logic, that is, the set of all wffs, corresponds to C ∗ , the intersection of all inductive sets w.r.t. B and F. By the unique readability theorem C ∗ is freely generated from the set of sentence symbols by the functions in F. This guarantees the uniqueness of the extensi ...
... The language of sentential logic, that is, the set of all wffs, corresponds to C ∗ , the intersection of all inductive sets w.r.t. B and F. By the unique readability theorem C ∗ is freely generated from the set of sentence symbols by the functions in F. This guarantees the uniqueness of the extensi ...
Binary Numbers
... Two’s complement notation: The most popular system for presenting integers within today’s computers is two’s complement notation. Each value is represented by a pattern of 32 bits. Such a large system allows a wide range of numbers to be represented. ...
... Two’s complement notation: The most popular system for presenting integers within today’s computers is two’s complement notation. Each value is represented by a pattern of 32 bits. Such a large system allows a wide range of numbers to be represented. ...
DOC - John Woods
... of a proof is a theorem. Note also that, when A is a theorem, the one-membered sequence (A) proves it to be. Semantics of (Model Theory)1 CPL Heads up: In logic the word “semantics” is misleading. It is a term antecedently in use by linguists to denote a theory of meaning, but in logic a semantics o ...
... of a proof is a theorem. Note also that, when A is a theorem, the one-membered sequence (A) proves it to be. Semantics of (Model Theory)1 CPL Heads up: In logic the word “semantics” is misleading. It is a term antecedently in use by linguists to denote a theory of meaning, but in logic a semantics o ...
The Axiom of Choice
... If you read about set theory, or take more advanced math classes, one thing you will almost certainly hear about is the axiom of choice. I thought you might like to hear a little bit about the axiom of choice, and related subjects. As you probably know, it is possible to make discussions involving s ...
... If you read about set theory, or take more advanced math classes, one thing you will almost certainly hear about is the axiom of choice. I thought you might like to hear a little bit about the axiom of choice, and related subjects. As you probably know, it is possible to make discussions involving s ...
Principia Mathematica
The Principia Mathematica is a three-volume work on the foundations of mathematics, written by Alfred North Whitehead and Bertrand Russell and published in 1910, 1912, and 1913. In 1927, it appeared in a second edition with an important Introduction To the Second Edition, an Appendix A that replaced ✸9 and an all-new Appendix C.PM, as it is often abbreviated, was an attempt to describe a set of axioms and inference rules in symbolic logic from which all mathematical truths could in principle be proven. As such, this ambitious project is of great importance in the history of mathematics and philosophy, being one of the foremost products of the belief that such an undertaking may be achievable. However, in 1931, Gödel's incompleteness theorem proved definitively that PM, and in fact any other attempt, could never achieve this lofty goal; that is, for any set of axioms and inference rules proposed to encapsulate mathematics, either the system must be inconsistent, or there must in fact be some truths of mathematics which could not be deduced from them.One of the main inspirations and motivations for PM was the earlier work of Gottlob Frege on logic, which Russell discovered allowed for the construction of paradoxical sets. PM sought to avoid this problem by ruling out the unrestricted creation of arbitrary sets. This was achieved by replacing the notion of a general set with the notion of a hierarchy of sets of different 'types', a set of a certain type only allowed to contain sets of strictly lower types. Contemporary mathematics, however, avoids paradoxes such as Russell's in less unwieldy ways, such as the system of Zermelo–Fraenkel set theory.PM is not to be confused with Russell's 1903 Principles of Mathematics. PM states: ""The present work was originally intended by us to be comprised in a second volume of Principles of Mathematics... But as we advanced, it became increasingly evident that the subject is a very much larger one than we had supposed; moreover on many fundamental questions which had been left obscure and doubtful in the former work, we have now arrived at what we believe to be satisfactory solutions.""The Modern Library placed it 23rd in a list of the top 100 English-language nonfiction books of the twentieth century.