| [[Directory:Jon_Awbrey/Papers/Propositional_Equation_Reasoning_Systems#Praeclarum_theorema|The first way of transforming the expression]] that appears on the left hand side of the equation can be described as ''proof-theoretic'' in character. | | [[Directory:Jon_Awbrey/Papers/Propositional_Equation_Reasoning_Systems#Praeclarum_theorema|The first way of transforming the expression]] that appears on the left hand side of the equation can be described as ''proof-theoretic'' in character. |