Along these lines, it has been proposed that the logical constants are just those expressions that can be characterized by a set of purely inferential introduction and elimination rules.[20] To grasp the meaning of the conjunction connective \(\dq{\and}\), for example, it is arguably sufficient to learn that it is governed by the rules: \begin{equation*} \frac{A, B}{A \and B} \quad \frac{A \and B}{A} \quad \frac{A \and B}{B} \end{equation*} Thus the meaning of \(\dq{\and}\) can be grasped by