Examples of using First-order logic in English and their translations into Vietnamese
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Colloquial
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Ecclesiastic
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Computer
Structures and first-order logic.
First-order logic is a particular formal system of logic….
There are two key parts of first-order logic.
In classical first-order logic, the definition of a structure prohibits the empty domain.[3].
Is not a sentence of first-order logic.
In first-order logic, one can quantify over individuals, but not over properties.
Many logics besides first-order logic are studied.
Sometimes"theory" is understood in a more formal sense,which is just a set of sentences in first-order logic.
Set theory, formalized using first-order logic, is the most common foundational system for mathematics.
Other classical logics[edit] Many logics besides first-order logic are studied.
While first-order logic allows for the use of predicates, such as"is a philosopher" in this example, propositional logic does not.[5].
From the model-theoretic point of view,structures are the objects used to define the semantics of first-order logic.
The syntax determines which finitesequences of symbols are legal expressions in first-order logic, while the semantics determine the meanings behind these expressions.
One of the interesting properties of periodic groups is that thedefinition cannot be formalized in terms of first-order logic.
Since they are logically valid in first-order logic with equality, they are not considered to be part of"the Peano axioms" in modern treatments.[5].
The 1928 first edition thereof is considered the first elementary textclearly grounded in the formalism now known as first-order logic(FOL).
Natural language understanding:Convert chunks of text into more formal representations such as first-order logic structures that are easier for computer programs to manipulate.
First-order logic quantifies only variables that range over individuals(elements of the domain of discourse); second-order logic, in addition, also quantifies over relations.
If the structure is considered in second-order logic instead of first-order logic, the definable sets of natural numbers in the resulting structure are classified in the analytical hierarchy.
In second-order logic, it is possible to define the addition and multiplication operations from the successor operation,but this cannot be done in the more restrictive setting of first-order logic.
The systems of propositional logic and first-order logic are the most widely studied today, because of their applicability to foundations of mathematics and because of their desirable proof-theoretic properties.
All of the Peano axioms except the ninth axiom(the induction axiom)are statements in first-order logic.[7] The arithmetical operations of addition and multiplication and the order relation can also be defined using first-order axioms.
First-order logic- also known as predicate logic, quantificational logic, and first-order predicate calculus- is a collection of formal systems used in mathematics, philosophy, linguistics, and computer science.
In logic and mathematics second-order logic is an extension of first-order logic, which itself is an extension of propositional logic.[1] Second-order logic is in turn extended by higher-order logic and type theory.
The adjective"first-order" distinguishes first-order logic from higher-order logic in which there are predicates having predicates or functions as arguments, or in which one or both of predicate quantifiers or function quantifiers are permitted.[3]: 56 In first-order theories, predicates are often associated with sets.
A theory about a topic is usually a first-order logic together with a specified domain of discourse over which the quantified variables range, finitely many functions from that domain to itself, finitely many predicates defined on that domain, and a set of axioms believed to hold for those things.
Both first-order and second-order logic use the idea of a domain of discourse(often called simply the"domain" or the"universe").
The next four are general statements about equality; in modern treatments these are often not taken as part of the Peano axioms,but rather as axioms of the"underlying logic".[3] The next three axioms are first-order statements about natural numbers expressing the fundamental properties of the successor operation.
Although modal logic is not often used to axiomatize mathematics, it has been used to study the properties of first-order provability(Solovay 1976) and set-theoretic forcing(Hamkins and Löwe 2007).
In mathematical logic, a definable set is an n-ary relation on the domain of a structure whose elements are precisely those elements satisfying some formula in the first-order language of that structure. A set can be defined with or without parameters, which are elements of the domain that can be referenced in the formula defining the relation.