A Package for Logical Symbols
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Tt-Satisfiable
CMPSCI 601: Recall From Last Time Lecture 6 Boolean Syntax: ¡ ¢¤£¦¥¨§¨£ © §¨£ § Boolean variables: A boolean variable represents an atomic statement that may be either true or false. There may be infinitely many of these available. Boolean expressions: £ atomic: , (“top”), (“bottom”) § ! " # $ , , , , , for Boolean expressions Note that any particular expression is a finite string, and thus may use only finitely many variables. £ £ A literal is an atomic expression or its negation: , , , . As you may know, the choice of operators is somewhat arbitary as long as we have a complete set, one that suf- fices to simulate all boolean functions. On HW#1 we ¢ § § ! argued that is already a complete set. 1 CMPSCI 601: Boolean Logic: Semantics Lecture 6 A boolean expression has a meaning, a truth value of true or false, once we know the truth values of all the individual variables. ¢ £ # ¡ A truth assignment is a function ¢ true § false , where is the set of all variables. An as- signment is appropriate to an expression ¤ if it assigns a value to all variables used in ¤ . ¡ The double-turnstile symbol ¥ (read as “models”) de- notes the relationship between a truth assignment and an ¡ ¥ ¤ expression. The statement “ ” (read as “ models ¤ ¤ ”) simply says “ is true under ”. 2 ¡ ¤ ¥ ¤ If is appropriate to , we define when is true by induction on the structure of ¤ : is true and is false for any , £ A variable is true iff says that it is, ¡ ¡ ¡ ¡ " ! ¥ ¤ ¥ ¥ If ¤ , iff both and , ¡ ¡ ¡ ¡ " ¥ ¤ ¥ ¥ If ¤ , iff either or or both, ¡ ¡ ¡ ¡ " # ¥ ¤ ¥ ¥ If ¤ , unless and , ¡ ¡ ¡ ¡ $ ¥ ¤ ¥ ¥ If ¤ , iff and are both true or both false. 3 Definition 6.1 A boolean expression ¤ is satisfiable iff ¡ ¥ ¤ there exists . -
Tilde-Arrow-Out (~→O)
Chapter 5: Derivations in Sentential Logic 181 atomic). In the next example, the disjunction is complex (its disjuncts are not atomic). Example 2 (1) (P ´ Q) → (P & Q) Pr (2) •: (P & Q) ∨ (~P & ~Q) ID (3) |~[(P & Q) ∨ (~P & ~Q)] As (4) |•: ¸ DD (5) ||~(P & Q) 3,~∨O (6) ||~(~P & ~Q) 3,~∨O (7) ||~(P ∨ Q) 1,5,→O (8) ||~P 7,~∨O (9) ||~Q 7,~∨O (10) ||~P & ~Q 8,9,&I (11) ||¸ 6,10,¸I The basic strategy is exactly like the previous problem. The only difference is that the formulas are more complex. 13. FURTHER RULES In the previous section, we added the rule ~∨O to our list of inference rules. Although it is not strictly required, it does make a number of derivations much easier. In the present section, for the sake of symmetry, we add corresponding rules for the remaining two-place connectives; specifically, we add ~&O, ~→O, and ~↔O. That way, we have a rule for handling any negated molecular formula. Also, we add one more rule that is sometimes useful, the Rule of Repetition. The additional negation rules are given as follows. Tilde-Ampersand-Out (~&O) ~(d & e) ––––––––– d → ~e Tilde-Arrow-Out (~→O) ~(d → f) –––––––––– d & ~f 182 Hardegree, Symbolic Logic Tilde-Double-Arrow-Out (~±O) ~(d ± e) –––––––––– ~d ± e The reader is urged to verify that these are all valid argument forms of sentential logic. There are other valid forms that could serve equally well as the rules in question. The choice is to a certain arbitrary. The advantage of the particular choice becomes more apparent in a later chapter on predicate logic. -
Chapter 9: Initial Theorems About Axiom System
Initial Theorems about Axiom 9 System AS1 1. Theorems in Axiom Systems versus Theorems about Axiom Systems ..................................2 2. Proofs about Axiom Systems ................................................................................................3 3. Initial Examples of Proofs in the Metalanguage about AS1 ..................................................4 4. The Deduction Theorem.......................................................................................................7 5. Using Mathematical Induction to do Proofs about Derivations .............................................8 6. Setting up the Proof of the Deduction Theorem.....................................................................9 7. Informal Proof of the Deduction Theorem..........................................................................10 8. The Lemmas Supporting the Deduction Theorem................................................................11 9. Rules R1 and R2 are Required for any DT-MP-Logic........................................................12 10. The Converse of the Deduction Theorem and Modus Ponens .............................................14 11. Some General Theorems About ......................................................................................15 12. Further Theorems About AS1.............................................................................................16 13. Appendix: Summary of Theorems about AS1.....................................................................18 2 Hardegree, -
Introducing Sentential Logic (SL) Part I – Syntax
Introducing Sentential Logic (SL) Part I – Syntax 1. As Aristotle noted long ago, some entailments in natural language seem to hold by dint of their “logical” form. Consider, for instance, the example of Aristotle’s being a logician above, as opposed to the “material” entailment considering the relative locations of Las Vegas and Pittsburgh. Such logical entailment provides the basic motivation for formal logic. So-called “formal” or “symbolic” logic is meant in part to provide a (perhaps idealized) model of this phenomenon. In formal logic, we develop an artificial but highly regimented language, with an eye perhaps of understanding natural language devices as approximating various operations within that formal language. 2. We’ll begin with a formal language that is commonly called either Sentential Logic (SL) or, more high- falutinly, “the propositional calculus.” You’re probably already quite familiar with it from an earlier logic course. SL is composed of Roman capital letters (and subscripted capital letters), various operators (or functors), and left and right parentheses. The standard operators for SL include the tilde (~), the ampersand (&), the wedge (v), and the arrow (→). Other operators, such as the double arrow, the stroke and the dagger, can easily be added as the need arises. The Syntax of S.L 3. A syntax for a language specifies how to construct meaningful expressions within that language. For purely formal languages such as SL, we can understand such expressions as well-formed formulas (wffs). The syntax of SL is recursive. That means that we start with basic (or atomic) wffs, and then specify how to build up more complex wffs from them. -
Chapter 13: Formal Proofs and Quantifiers
Chapter 13: Formal Proofs and Quantifiers § 13.1 Universal quantifier rules Universal Elimination (∀ Elim) ∀x S(x) ❺ S(c) Here x stands for any variable, c stands for any individual constant, and S(c) stands for the result of replacing all free occurrences of x in S(x) with c. Example 1. ∀x ∃y (Adjoins(x, y) ∧ SameSize(y, x)) 2. ∃y (Adjoins(b, y) ∧ SameSize(y, b)) ∀ Elim: 1 General Conditional Proof (∀ Intro) ✾c P(c) Where c does not occur outside Q(c) the subproof where it is introduced. ❺ ∀x (P(x) → Q(x)) There is an important bit of new notation here— ✾c , the “boxed constant” at the beginning of the assumption line. This says, in effect, “let’s call it c.” To enter the boxed constant in Fitch, start a new subproof and click on the downward pointing triangle ❼. This will open a menu that lets you choose the constant you wish to use as a name for an arbitrary object. Your subproof will typically end with some sentence containing this constant. In giving the justification for the universal generalization, we cite the entire subproof (as we do in the case of → Intro). Notice that although c may not occur outside the subproof where it is introduced, it may occur again inside a subproof within the original subproof. Universal Introduction (∀ Intro) ✾c Where c does not occur outside the subproof where it is P(c) introduced. ❺ ∀x P(x) Remember, any time you set up a subproof for ∀ Intro, you must choose a “boxed constant” on the assumption line of the subproof, even if there is no sentence on the assumption line. -
Logic and Proof Release 3.18.4
Logic and Proof Release 3.18.4 Jeremy Avigad, Robert Y. Lewis, and Floris van Doorn Sep 10, 2021 CONTENTS 1 Introduction 1 1.1 Mathematical Proof ............................................ 1 1.2 Symbolic Logic .............................................. 2 1.3 Interactive Theorem Proving ....................................... 4 1.4 The Semantic Point of View ....................................... 5 1.5 Goals Summarized ............................................ 6 1.6 About this Textbook ........................................... 6 2 Propositional Logic 7 2.1 A Puzzle ................................................. 7 2.2 A Solution ................................................ 7 2.3 Rules of Inference ............................................ 8 2.4 The Language of Propositional Logic ................................... 15 2.5 Exercises ................................................. 16 3 Natural Deduction for Propositional Logic 17 3.1 Derivations in Natural Deduction ..................................... 17 3.2 Examples ................................................. 19 3.3 Forward and Backward Reasoning .................................... 20 3.4 Reasoning by Cases ............................................ 22 3.5 Some Logical Identities .......................................... 23 3.6 Exercises ................................................. 24 4 Propositional Logic in Lean 25 4.1 Expressions for Propositions and Proofs ................................. 25 4.2 More commands ............................................ -
1 Symbols (2286)
1 Symbols (2286) USV Symbol Macro(s) Description 0009 \textHT <control> 000A \textLF <control> 000D \textCR <control> 0022 ” \textquotedbl QUOTATION MARK 0023 # \texthash NUMBER SIGN \textnumbersign 0024 $ \textdollar DOLLAR SIGN 0025 % \textpercent PERCENT SIGN 0026 & \textampersand AMPERSAND 0027 ’ \textquotesingle APOSTROPHE 0028 ( \textparenleft LEFT PARENTHESIS 0029 ) \textparenright RIGHT PARENTHESIS 002A * \textasteriskcentered ASTERISK 002B + \textMVPlus PLUS SIGN 002C , \textMVComma COMMA 002D - \textMVMinus HYPHEN-MINUS 002E . \textMVPeriod FULL STOP 002F / \textMVDivision SOLIDUS 0030 0 \textMVZero DIGIT ZERO 0031 1 \textMVOne DIGIT ONE 0032 2 \textMVTwo DIGIT TWO 0033 3 \textMVThree DIGIT THREE 0034 4 \textMVFour DIGIT FOUR 0035 5 \textMVFive DIGIT FIVE 0036 6 \textMVSix DIGIT SIX 0037 7 \textMVSeven DIGIT SEVEN 0038 8 \textMVEight DIGIT EIGHT 0039 9 \textMVNine DIGIT NINE 003C < \textless LESS-THAN SIGN 003D = \textequals EQUALS SIGN 003E > \textgreater GREATER-THAN SIGN 0040 @ \textMVAt COMMERCIAL AT 005C \ \textbackslash REVERSE SOLIDUS 005E ^ \textasciicircum CIRCUMFLEX ACCENT 005F _ \textunderscore LOW LINE 0060 ‘ \textasciigrave GRAVE ACCENT 0067 g \textg LATIN SMALL LETTER G 007B { \textbraceleft LEFT CURLY BRACKET 007C | \textbar VERTICAL LINE 007D } \textbraceright RIGHT CURLY BRACKET 007E ~ \textasciitilde TILDE 00A0 \nobreakspace NO-BREAK SPACE 00A1 ¡ \textexclamdown INVERTED EXCLAMATION MARK 00A2 ¢ \textcent CENT SIGN 00A3 £ \textsterling POUND SIGN 00A4 ¤ \textcurrency CURRENCY SIGN 00A5 ¥ \textyen YEN SIGN 00A6 -
Data Stream Algorithms Lecture Notes
CS49: Data Stream Algorithms Lecture Notes, Fall 2011 Amit Chakrabarti Dartmouth College Latest Update: October 14, 2014 DRAFT Acknowledgements These lecture notes began as rough scribe notes for a Fall 2009 offering of the course “Data Stream Algorithms” at Dartmouth College. The initial scribe notes were prepared mostly by students enrolled in the course in 2009. Subsequently, during a Fall 2011 offering of the course, I edited the notes heavily, bringing them into presentable form, with the aim being to create a resource for students and other teachers of this material. I would like to acknowledge the initial effort by the 2009 students that got these notes started: Radhika Bhasin, Andrew Cherne, Robin Chhetri, Joe Cooley, Jon Denning, Alina Dja- mankulova, Ryan Kingston, Ranganath Kondapally, Adrian Kostrubiak, Konstantin Kutzkow, Aarathi Prasad, Priya Natarajan, and Zhenghui Wang. DRAFT Contents 0 Preliminaries: The Data Stream Model 5 0.1 TheBasicSetup................................... ........... 5 0.2 TheQualityofanAlgorithm’sAnswer . ................. 5 0.3 VariationsoftheBasicSetup . ................ 6 1 Finding Frequent Items Deterministically 7 1.1 TheProblem...................................... .......... 7 1.2 TheMisra-GriesAlgorithm. ............... 7 1.3 AnalysisoftheAlgorithm . .............. 7 2 Estimating the Number of Distinct Elements 9 2.1 TheProblem...................................... .......... 9 2.2 TheAlgorithm .................................... .......... 9 2.3 TheQualityoftheAlgorithm’sEstimate . .................. -
1. Latex and Symbolic Logic: an Introduction
Symbolic Logic and LATEX David W. Agler June 21, 2013 1 Introduction This document introduces some features of LATEX, the special symbols you will need in Symbolic Logic (PHIL012), and some reasons for why you should use LATEX over traditional word processing programs. This video also ac- companies several video tutorials on how to use LATEX in the Symbolic Logic (PHIL012) course at Penn State. 2 LATEX is not a word processor LATEX is a typesetting system that was originally designed to produce docu- ments with special symbols. LATEX is not a word processor which coordinates text with styling simultaneously. Instead, the LATEX system separates text from styling as it consists of (i) a text document (or *.tex file) which is text that does not contain any formatting and (ii) a compiler that takes the *.tex file and turns it into a readable and professionally stylized document. In other words, the production of a document using LATEX begins with the specification of what you want to say and the structure of what you want to say and this is then processed by a compiler which styles your document. To get a clearer idea of what some of this means, let's look at a very simple LATEX source document: \documentclass[12pt]{article} \begin{document} \title{Symbolic Logic and \LaTeX\ } \author{David W. Agler} 1 \date{\today} \maketitle \section{Introduction} Hello Again World! \end{document} The above specifies the class (or kind) of document you want to produce (an article, rather than a book or letter), commands for begining the document, the title of the article, the author of the article, the date, a command to make the title, a section that will automatically be numbered, some content that will appear as text (\Hello World"), and finally a command to end the document. -
The Comprehensive LATEX Symbol List
The Comprehensive LATEX Symbol List Scott Pakin <[email protected]>∗ 22 September 2005 Abstract This document lists 3300 symbols and the corresponding LATEX commands that produce them. Some of these symbols are guaranteed to be available in every LATEX 2ε system; others require fonts and packages that may not accompany a given distribution and that therefore need to be installed. All of the fonts and packages used to prepare this document—as well as this document itself—are freely available from the Comprehensive TEX Archive Network (http://www.ctan.org/). Contents 1 Introduction 6 1.1 Document Usage . 6 1.2 Frequently Requested Symbols . 6 2 Body-text symbols 7 Table 1: LATEX 2ε Escapable “Special” Characters . 7 Table 2: Predefined LATEX 2ε Text-mode Commands . 7 Table 3: LATEX 2ε Commands Defined to Work in Both Math and Text Mode . 7 Table 4: AMS Commands Defined to Work in Both Math and Text Mode . 7 Table 5: Non-ASCII Letters (Excluding Accented Letters) . 8 Table 6: Letters Used to Typeset African Languages . 8 Table 7: Letters Used to Typeset Vietnamese . 8 Table 8: Punctuation Marks Not Found in OT1 . 8 Table 9: pifont Decorative Punctuation Marks . 8 Table 10: tipa Phonetic Symbols . 9 Table 11: tipx Phonetic Symbols . 10 Table 13: wsuipa Phonetic Symbols . 10 Table 14: wasysym Phonetic Symbols . 11 Table 15: phonetic Phonetic Symbols . 11 Table 16: t4phonet Phonetic Symbols . 12 Table 17: semtrans Transliteration Symbols . 12 Table 18: Text-mode Accents . 12 Table 19: tipa Text-mode Accents . 12 Table 20: extraipa Text-mode Accents . -
Non-Adaptive Adaptive Sampling on Turnstile Streams
Non-Adaptive Adaptive Sampling on Turnstile Streams Sepideh Mahabadi∗ Ilya Razenshteyn† David P. Woodruff‡ Samson Zhou§ April 24, 2020 Abstract Adaptive sampling is a useful algorithmic tool for data summarization problems in the clas- sical centralized setting, where the entire dataset is available to the single processor performing the computation. Adaptive sampling repeatedly selects rows of an underlying matrix A Rn×d, where n d, with probabilities proportional to their distances to the subspace of the previously∈ selected rows.≫ Intuitively, adaptive sampling seems to be limited to trivial multi-pass algorithms in the streaming model of computation due to its inherently sequential nature of assigning sam- pling probabilities to each row only after the previous iteration is completed. Surprisingly, we show this is not the case by giving the first one-pass algorithms for adaptive sampling on turnstile streams and using space poly(d, k, log n), where k is the number of adaptive sampling rounds to be performed. Our adaptive sampling procedure has a number of applications to various data summariza- tion problems that either improve state-of-the-art or have only been previously studied in the more relaxed row-arrival model. We give the first relative-error algorithm for column subset selection on turnstile streams. We show our adaptive sampling algorithm also gives the first relative-error algorithm for subspace approximation on turnstile streams that returns k noisy rows of A. The quality of the output can be improved to a (1+ǫ)-approximation at the tradeoff of a bicriteria algorithm that outputs a larger number of rows. -
Basics of Type Theory and Coq Logic Types ∧, ∨, ⇒, ¬, ∀, ∃ ×, +, →, Q, P Michael Shulman
Type-theoretic foundations Set theory Type theory Basics of type theory and Coq Logic Types ^; _; ); :; 8; 9 ×; +; !; Q; P Michael Shulman Sets Logic January 31, 2012 ×; +; !; Q; P ^; _; ); :; 8; 9 x 2 A is a proposition x : A is a typing judgment 1 / 77 2 / 77 Type theory is programming Typing judgments Type theory consists of rules for manipulating judgments. The most important judgment is a typing judgment: x1 : A1; x2 : A2;::: xn : An ` b : B For now, think of type theory as a programming language. The turnstile ` binds most loosely, followed by commas. • Closely related to functional programming languages like This should be read as: ML, Haskell, Lisp, Scheme. In the context of variables x of type A , x of type A ,..., • More expressive and powerful. 1 1 2 2 and xn of type An, the expression b has type B. • Can manipulate “mathematical objects”. Examples ` 0: N x : N; y : N ` x + y : N f : R ! R; x : R ` f (x): R 1 (n) 1 f : C (R; R); n: N ` f : C (R; R) 4 / 77 5 / 77 Type constructors Derivations The basic rules tell us how to construct valid typing judgments, We write these rules as follows. i.e. how to write programs with given input and output types. This includes: ` A: Type ` B : Type 1 How to construct new types (judgments Γ ` A: Type). ` A ! B : Type 2 How to construct terms of these types. 3 How to use such terms to construct terms of other types. x : A ` b : B A Example (Function types) ` λx :b : A ! B 1 If A: Type and B : Type, then A ! B : Type.