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For consistency use the following preferred symbols and terminology in Logic articles

It is useful to have an agreed set of symbols and terminolgy. Not only do symbols vary from author to author, but any symbol may be written in a variety of fonts which may or may not appear on various browsers. The aim is consistency and legibility

Contents 1 Symbols 1.1 Truth Functional Connectives 1.2 Quantifiers 1.3 Metalogical Symbols 2 Terminolgy

[edit] Symbols

For consistency use the following preferred symbols in Logic articles:

[edit] Truth Functional Connectives

Connective	Name	Symbol(s)	Preferred Symbol(s)	Template	<math>	See
Negation	NOT	¬ or ¬ or ~	¬	{{not}}	\neg	Logical negation
Conjunction	AND	or &	&	{{and}}	&	Logical conjunction
Inclusive disjunction	OR			{{or-}}	\vee	Logical disjunction
Material implication	IMPLIES	or or or		{{imp}}	\rightarrow	Material conditional
Material equivalence (biconditional)	EQV or XNOR	or or =		{{eqv}}	\leftrightarrow	Logical biconditional
Identity (definition)	IS	or := or =		{{ident}}	\equiv	Law of identity
Neither-nor (joint denial)	NOR	↓ or  ↓	↓	{{nor-}}	\downarrow	Logical NOR
Not both (alternative denial)	NAND	↑	↑	{{nand}}	\uparrow	Alternative denial (nand)
Exclusive disjunction	XOR	or + or or ≠		{{xor}}	\nleftrightarrow	XOR

[edit] Quantifiers

Quantifier	Description	Symbols	Preferred Symbol	Template	<math>
Universal	For every x	(x) or x or		{{all}}	\forall x
Existential	There exists an x	x or		{{exist}}	\exists x

[edit] Metalogical Symbols

Name	Description/Usage	Symbol(s)	Preferred Symbol(s)	Template	<math>	See
Theorem	, ,			{{tee}}	\vdash	Turnstile (symbol)
Semantic Entailment, Logical Implication	,			{{models}}	\models	Logical implication
True, tautology		or T or 1		{{true}}	\top	Tautology (logic)
False, contradiction		or F or 0		{{false}}	\bot	Logical value

[edit] Terminolgy

For consistency use the following terminology in Logic articles: To be drafted