CHICAGO — NOW that the dust is settling from the Supreme Court’s decision in Obergefell v. Hodges, which recognized a right to same-sex marriage, there are new questions. In particular, could the decision presage a constitutional right to plural marriage? If there is no magic power in opposite sexes when it comes to marriage, is there any magic power in the number two?

Chief Justice John G. Roberts Jr.’s dissent in Obergefell raised this very question, intending to show how radical the majority’s decision could become. But the issue was hard to discuss candidly while same-sex marriage was still pending, because both sides knew that association with plural marriage, a more unpopular cause, could have stymied progress for gay rights. (Opponents of same-sex marriage had reasons to emphasize the association, while supporters had reasons to play it down.) With same-sex marriage on the books, we can now ask whether polyamorous relationships should be next.

There is a very good argument that they should. Justice Anthony M. Kennedy’s majority opinion in Obergefell did not focus primarily on the issue of sexual orientation. Instead, its main focus was on a “fundamental right to marry” — a right that he said could not be limited to rigid historical definitions or left to the legislative process. That right was about autonomy and fulfillment, about child rearing and the social order. By those lights, groups of adults who have profound polyamorous attachments and wish to build families and join the community have a strong claim to a right to marry.

And while Justice Kennedy’s opinion does not explicitly discuss this possibility, it is easy to see how future generations could read his language to include polyamory or plural marriage. Earlier court decisions about marriage, Justice Kennedy wrote, had “presumed a relationship involving opposite-sex partners,” but now we understand that the presumption was wrong. Similarly, while Justice Kennedy’s opinion repeatedly presumes that marriage involves two people, it is not hard to imagine another justice in 20 or 40 years saying that the assumption is similarly unenlightened. (It is even conceivable that Justice Kennedy himself anticipated that possibility.)