From Justice Alito's dissent in United States v. Windsor (pp. 14-15, n.7, some citations and internal parentheticals omitted, emphasis added):
The degree to which this question is intractable to typical judicial processes of decisionmaking was highlighted by the trial in Hollingsworth v. Perry. In that case, the trial judge, after receiving testimony from some expert witnesses, purported to make "findings of fact" on such questions as why marriage came to be, what marriage is, and the effect legalizing same-sex marriage would have on opposite-sex marriage.
At times, the trial reached the heights of parody, as when the trial judge questioned his ability to take into account the views of great thinkers of the past because they were unavailable to testify in person in his courtroom.
And, if this spectacle were not enough, some professors of constitutional law have argued that we are bound to accept the trial judge's findings—including those on major philosophical questions and predictions about the future—unless they are "clearly erroneous." See Brief for Constitutional Law and Civil Procedure Professors as Amici Curiae in Hollingsworth v. Perry ("[T]he district court’s factual findings are compelling and should be given significant weight"); ("Under any standard of review, this Court should credit and adopt the trial court's findings because they result from rigorous and exacting application of the Federal Rules of Evidence, and are supported by reliable research and by the unanimous consensus of mainstream social science experts"). Only an arrogant legal culture that has lost all appreciation of its own limitations could take such a suggestion seriously.