Defining what constitutes pornography has always been a bit of a struggle. It was Supreme Court Justice Potter Stewart who once illustrated the difficulty by giving his own subjective definition: “I know it when I see it.”
I just read today that Carl Trueman has found as good a definition as I have ever seen, and he got it from The Catechism of the Catholic Church. Here it is:
2354: Pornography consists in removing real or simulated sexual acts from the intimacy of the partners, in order to display them deliberately to third parties. It offends against chastity because it perverts the conjugal act, the intimate giving of spouses to each other. It does grave injury to the dignity of its participants (actors, vendors, the public), since each one becomes an object of base pleasure and illicit profit for others. It immerses all who are involved in the illusion of a fantasy world. It is a grave offense. Civil authorities should prevent the production and distribution of pornographic materials.
Truman says this: “This seems to me to be pretty thorough and the kind of statement which also repays careful pastoral reflection, as it highlights numerous ways in which the phenomenon is damaging to all concerned.” I agree.