For some years now, American society has been discussing the meaning of marriage. Last November 5, I had the opportunity to attend to an academic discussion between two people who have reflected on the issue. The contestants were a young researcher, Sherif Girgis, co-author of the widely distributed study What is Marriage? ( more than 70,000 downloads on the database: Social Science Research Network); and his former professor Stephen Macedo, a political philosopher and author of numerous publications in defense of same-sex marriage. They debated before a group of professors and students gathered at classroom McCosh 50, one of the largest at Princeton University. The audience included people of varying sensibilities. Among the best known were Peter Singer (an advocate of animal rights and the lack of rights for babies with severe mental disabilities) and Philip Pettit (ideological inspiration for former Spanish President Zapatero). Girgis defended that, if we review the traditional definition of marriage, naturally oriented to procreation (although this does not always occur), there is no solid rational principle to exclude from it any other form of loving sexual cohabitation. Macedo argued that there is - a position that Peter Singer criticized as conservative. The discussion was respectful and, most importantly, focused on the central question, which vague references to equality and freedom often obscure: what is marriage?

On June 26, the U.S. Supreme Court largely interrupted this deliberation. Its decision was to be expected, judging by the composition of the Court. In rulings of this subject, ideological reasoning plays a greater role than technicalities, given that the Constitution includes abstractions (liberty, equality, etc.) that can be interpreted in opposite directions. In the absence of a consensus on the method of interpretation, i.e., a rule that effectively compels to interpret the Constitution in a certain way, moral and ideological convictions compensate for the vagueness of the text. Everyone knew that four of the justices (nominated by Republican presidents) would not recognize a right to same-sex marriage. Likewise, everyone knew that four others (nominated by Democratic presidents) would vote in favor of such a right. And everyone knew that Justice Anthony Kennedy (nominated by Ronald Reagan in 1987, following a historic political campaign in the Senate that stopped his attempt to appoint another more conservative justice) would break the tie, almost certainly in favor of the second group.

Passed by a slim majority, the ruling opens by declaring that "the Constitution promises liberty to all within its confines". Now, before being a liberty, marriage is an institution. Freedom of access to the institution presupposes the integrity of the institution. And, when a modification of the institution brings about a substantial change in its meaning, sooner or later the new principles must run their course and give way to new reforms. This was what was being discussed in the discussion to which I referred in the first paragraph, a dispute of which there is hardly a trace in the Judgment. It is thus clear that the hegemony that the speech of rights and liberties exercises over public life is a dangerous solvent for rational political discussion, as Harvard professor Mary Ann Glendon pointed out years ago.

The Supreme Court's decision also raises another problem: that there is no constituent consensus on this issue among the U.S. states. In the words of Justice Samuel Alito's dissenting opinion, "while, for many, the features of marriage in the 21st century have changed, those states that do not want to recognize same-sex marriage have not abandoned the traditional understanding. They fear that, by officially abandoning the old understanding, they may contribute to the further decline of marriage." Alito concludes, "it falls far outside the bounds of this Court's authority to say that a state cannot adhere to the conception of marriage that has prevailed for so long, not only in this country and others with similar cultural roots, but in a wide variety of countries and cultures around the world." The decision on the 26th did not simply approve same-sex marriage, but prohibited individual state parliaments from adhering to the traditional view. In my opinion, the speech of "legal equality" has devastated the positive legal meaning of the institution of marriage. I also think that there is a certain risk that the speech of "real equality" will override the freedom to defend this meaning in public.