First Order Logic (FOL)

View
FOL is often called the language of computer science. It has far more powerful constructs than PL and is more expressive. Unlike PL, FOL describes objects and their inter-relationships and incorporates the concept of quantifiers. Quantifiers allow you to express properties shared (or not shared) by sets of objects.

First order logic is a type of logic which is used in certain branches of mathematics and philosophy. First order logic enables the definition of a syntax which is independent of the mathematical or logical terms.

In first order logic, reasoning can be done from two points of view: either using syntax alone, or including semantic terms. First order logic is different from propositional logic: In first order logic, there are quantifiers, called for all (written as ∀) and there is at least one (written as ∃). Negation, conjunction, inclusive disjunction, exclusive disjunction and implication are all defined the same way as in propositional logic. Because of that, first order logic can be thought of as an extension of propositional logic.

The completeness of first order logic, the result which asserts the equivalence between valid formulas and formal theorems, is established by Gödel. Together with Zermelo–Fraenkel set theory, first order logic is the foundation of many branches of modern mathematics.


Source: Wikipedia, https://simple.wikipedia.org/wiki/First_order_logic
Creative Commons License This work is licensed under a Creative Commons Attribution-ShareAlike 4.0 License.