Logical derivation

A step-by-step proof showing how a conclusion follows from premises using Inference rules - each step applies a rule to previous steps; in type systems, a Derivation tree is a derivation proving that an

A step-by-step proof showing how a conclusion follows from premises using Inference rules - each step applies a rule to previous steps; in type systems, a Judgment tree is a derivation proving that an expression has a certain type.