Modus ponens

Modus ponens comes from the Latin “method of affirming (the antecedent)”. Sometimes referred to as “elimination of the implication” ($\to E$): ?

$$\frac{A,A\to B}{B}(\to E)\text{ or "modus ponens"}$$

For example, if A was born in Britain, they are British. A was born in Britain. Therefore, A is British.