"Remember the good things that you hear, and do not consider who says them," counseled Thomas Aquinas in the 13th century. The source of an apparent pearl of wisdom is often irrelevant. Yeats highlighted our universal connection: "If what I say resonates with you, it's merely because we are both branches on the same tree."
Those who appear to be "enemies" may be better understood as social critics who have important feedback to give us. Jeff Schmidt wrote:
"Professionals generally avoid the risk inherent in real critical thinking and cannot properly be called critical thinkers. They are simply ideologically disciplined thinkers. Real critical thinking means uncovering and questioning social, political and moral assumptions; applying and refining a personally developed worldview; and calling for action that advances a personally created agenda. An approach that backs away from any of these three components lacks the critical spirit."
Nikki Stern noted the tendency to ostracize even those allies who attempt to understand the true enemy:
"[William] Bennett [in his 2002 book Why We Fight: Moral Clarity and the War on Terrorism] focused on [Ward] Churchill's statement [describing World Trade Center workers as "little Eichmanns"] in order to launch an attack against 'terrorist sympathizers.' The group included those who were trying to understand the underlying ideology that motivates terrorism."
Rollo May pointed out that brave, nonconformist thinking is often an especially effective deliverer of wisdom. "The authentic rebel knows," he wrote, "that the silencing of his adversaries is the last thing on earth he wishes: their extermination would deprive him and whoever else remains alive from the uniqueness, the originality, and the capacity for insight that these enemies – being human – also have and could share with him. ... We would lose not only our enemies' good ideas, but the restraints they give us as well." Consider that we sometimes inflate the value of what our friends say, and are inclined to discount what our enemies say; so, if our enemies seem to be telling us something true and good, that counterintuitive situation is an indicator of the rightness of what they are saying.
The musician Jascha Heifetz said: “No matter what side of an argument you're on, you always find some people on your side that you wish were on the other side.” To understand this, one might refer to a phrase circulated on the Internet in 2015: "You're not wrong, you're just an asshole," to which someone coined the fake German word Waltersobchakeit, based on the character Walter Sobchak from the movie "The Big Lebowski." To paraphrase it one more time, the tone in which a statement is delivered can make a true or moral statement seem unpalatable, or, vice versa, a false or immoral statement seem appealing. It is important to cultivate a proper tone. Alfred North Whitehead said, "It is a disease of philosophy when it is neither bold nor humble, but merely a reflection of the temperamental presuppositions of exceptional personalities."
To add yet another dimension: One's history of perceiving a person as generally saying things that are good (or bad) may serve as a reason to forgive (or to refuse to forgive) a one-time deviation from their norm. There is no known word for this.
Thomas Aquinas, quoted by Mary Daly, The Church and the Second Sex, New York: Harper and Row, 1968. p 15.
William Butler Yeats
Jeff Schmidt. Disciplined Minds: A Critical Look at Salaried Professionals and the Soul-Battering System that Shapes Their Lives. (Rowman & Littlefield, 2000) Kindle Edition.
Nikki Stern. Because I Say So: The Dangerous Appeal of Moral Authority. Bascom Hill Books, 2010. p. 47.
Rollo May, Power and Innocence: A Search for the Sources of Violence, New York: W. W. Norton and Co., 1972. p 237.
Jascha Heifetz, quoted in the Associated Press. Quoted in The Week. Aug. 9, 2013. p. 15.
Alfred North Whitehead. Process and Reality. (Originally 1929.) Part 1, Chap. 1, Sect. 6. New York: Harper, 1960. p 24.