liberal

"A liberal is a man too broadminded to take his own side in a quarrel." - Robert Frost

quoted in the footnotes by Cuddihy (see tolerance and realism)

tolerance and realism

"Tolerance is the virtue of a man without convictions." - G. K. Chesterton.
«Толерантность – это добродетель людей, которые ни во что не верят». – Г. К. Честертон

American theologian Reinhold Niebuhr says (as quoted here): “Our toleration of truths opposed to those which we confess is an expression of the spirit of forgiveness in the realm of culture. Like all forgiveness, it is possible only if we are not too sure of our own virtue. Loyalty to the truth requires confidence in the possibility of its attainment; toleration of others requires broken confidence in the finality of our own truth.”

это упоминает John Murray Cuddihy in No Offense: Civil Religion and Protestant Taste - не зря купил, как и The Ordeal of Civility.

see also Niebuhr's Christian Realism [НИБУР (Niebuhr) Райнхольд - один из основоположников диалектической теологии.]