Cardinal Donald Wuerl's opinion on the nature of marriage appearing on the July 5 Opinion page needs to be taken with a grain of salt.
First of all, Cardinal Wuerl is an archbishop of the Catholic Church and, while demanding respect, does not have an unbiased view of what marriage is or should be.
Second, Cardinal Wuerl's fundamental principle, that the meaning of marriage is "intrinsic, grounded in human nature and discoverable by human reason" is false. Meaning is not something sitting around waiting to be discovered. It evolves as a result of human interaction. Just as the meaning of marriage is in the process of evolving today.