⊨

Math Operator 165

Unicode
U+22A8
Category
Math
HTML Entity
⊨
CSS
\22A8
The ⊨ symbol, officially named 'True' in Unicode but widely known as the 'Double Turnstile,' is a mathematical operator heavily used in formal logic. It represents semantic entailment, meaning that a specific set of statements logically guarantees a certain conclusion. You'll primarily encounter this symbol in advanced computer science, philosophy, and mathematical logic texts to show that a structure 'models' a formula.

How to Type

Windows
Type 22A8 then press Alt+X (in Microsoft Word), or Win+. and search 'true'
macOS
Control+Command+Space, then search 'double turnstile' or 'true'
Linux
Ctrl+Shift+U then 22A8 and press Enter
HTML
⊧ or ⊨

In Programming

In computer science, type theory, and formal verification, ⊨ is used in proofs to denote semantic entailment or that a given state satisfies a proposition. In LaTeX formatting, it is rendered using the \models or \vDash commands.

Read full meaning article

Tags

LaTeX vDash \vDash computer science double bar turnstile double turnstile entails entails symbol formal logic logic logical truth mathematics model theory philosophy of logic semantic consequence semantic entailment tautology true

Related Symbols

± Plus Minus Sign × Multiplication Sign ÷ Division Sign ≠ Not Equal To ≈ Approximately Equal To ∞ Infinity √ Square Root ∑ Summation ∫ Integral π Pi ≤ Less Than or Equal To ≥ Greater Than or Equal To