Jaśkowski's calculus

Jaśkowski's calculus is a logical system that uses a special method called "natural deduction" to determine if a statement logically follows from other statements. It relies on clear rules for how to combine assumptions and derive conclusions step-by-step, often involving a device called "discharging" assumptions when they are no longer needed. This approach makes it easier to understand how conclusions are reached and to verify their correctness. Essentially, Jaśkowski's calculus provides a structured, disciplined way to analyze and prove logical statements systematically.