Logic

Conjunction

Natural deduction

Classical logic

Multi-valued logic

Complement

Closed set

Homeomorphism

Separation axiom

Embedding

Three-way comparison

NOT

OR

AND

Boolean logic

XOR function

Modus Tollens

Modus Ponens

Deductive Reasoning

Horn Clause

ACL2

propositional logic

symbolic representation

Theorem proving

Recursive functionals

Recursive functions

Principia Mathematica

Symbolic logic

Logical functions

Type theory

Gödel's incompleteness theorems

Ordinal logics

Lambda calculus

Computability

Halting problem

On Computable Numbers, with an Application to the Entscheidungsproblem

Entscheidungsproblem

Mathematical logic

fuzzy logic

First-order logic