Oliver Wendell Holmes famously wrote, “The life of the law has not been logic; it has been experience.”  In various writings, he expanded that claim, contrasting a natural law approach to justifying legal and ethical rules of conduct with his own more modest approach rooted in history and experience and falling under the broad perspective labeled pragmatism. Since religion in general and Mormonism in particular have many rules of conduct for which a variety of justifications grounded in natural law, experience, and history are held out, Holmes’ approach may shed some light on how we do this.
Holmes didn’t like the natural law approach. He wrote that “there is in all men a demand for the superlative …. It seems to me that this demand is at the bottom of the philosopher’s effort to prove that truth is absolute and of the jurist’s search for criteria of universal validity which he collects under the head of natural law.” 
It was this notion that defensible rules of conduct must be based on absolute truth and be of universal validity, applicable in all times and seasons, that rankled Holmes, who worked with an alternative and more pragmatic definition of truth. “When I say that a thing is true, I mean that I cannot help believing it. I am stating an experience as to which there is no choice.”  He went so far as to make the absolutist outlook a function of the absolutist’s own personal experience rather than any contact with the Absolute:
What we most love and revere generally is determined by early associations. … But while one’s experience thus makes certain preferences dogmatic for oneself, recognition of how they came to be so leaves one able to see that others, poor souls, may be equally dogmatic about something else. … Deep-seated preferences can not be argued about — you can not argue a man into liking a glass of beer.” 
So Holmes rejected universal validity as a useful or meaningful standard and suggested those who argue dogmatically have simply never reflected on how they come to hold their own beliefs. Here is a fuller statement of his alternative approach:
[I]t is true, no doubt, that an evolutionist [i.e., one who bases convictions in experience and history rather than in natural law] will hesitate to affirm universal validity for his social ideals …. He is content if he can prove them best for here and now. He may be ready to admit that he knows nothing about an absolute best in the cosmos, and even that he knows next to nothing about a permanent best for men. Still it is true that a body of law is more rational and more civilized when every rule it contains is referred articulately and definitely to an end which is subserves, and when the grounds for desiring that end are stated or are ready to be stated in words. 
In this and other passages, Holmes argues for explicitly stating the end to be served, the grounds for adopting that end, the balance between the benefits of that end and the opportunity costs of achieving it, and whether appropriate means for bringing about that end are available. Holmes also proposes using this sort of instrumental reasoning rather than relying on any simple appeal to inherited rules and tradition. He quipped: “It is revolting to have no better reason for a rule of law than that it was laid down in the time of Henry IV.” 
So here’s the question: Does this preference for experience over logic, for explicitly justifying rules and policies by the ends to be achieved, find any echo in Mormonism? Does the approach Holmes endorsed bear any resemblance to the way Mormons typically approach questions of doctrine and practice? It is not hard to find good examples suggesting parallels.
First, the LDS view does not see God’s ends and purposes as inscrutable. They are spelled out quite clearly, at least for us here on Planet Earth:
And the Lord God spake unto Moses, saying: The heavens, they are many, and they cannot be numbered unto man; but they are numbered unto me, for they are mine.
And as one earth shall pass away, and the heavens thereof even so shall another come; and there is no end to my works, neither to my words.
For behold, this is my work and my gloryâ€”to bring to pass the immortality and eternal life of man. (Moses 1:37-39)
Second, the doctrine of continuing revelation means that no doctrine or interpretation can ever be definitively affirmed as God’s final word. If the historical record of how LDS leaders struggled for most of our history with the question of who can or cannot receive the priesthood teaches us anything, it is that God lets us muddle through even fundamental doctrines for ourselves for long periods. It should be no surprise if the resulting practices and policies are, as Holmes termed them, “the best for here and now” but which may nevertheless be (and sometimes are) superseded at a later time by updated or improved practices and policies. No pragmatist could ask for more.
Third, the LDS view does not require or even recommend reliance on received wisdom or blind faith. “And as all have not faith, seek ye diligently and teach one another words of wisdom; yea, seek ye out of the best books words of wisdom; seek learning, even by study and also by faith” (D&C 88:118). Even revelation comes after a process of reasoning and reflection: “I say unto you, that you must study it out in your mind; then you must ask me if it be right …” (D&C 9:8).
Fourth, as a doctrinal example, consider the Word of Wisdom, defined at LDS.org as “a law of health revealed by the Lord for the physical and spiritual benefit of His children.” (Notice how, following Holmes, the goal or end is explicitly stated.) The actual content of the Word of Wisdom has changed over the years. In other words, it has developed or evolved over the course of LDS history. And from the perspective of a religious pragmatist, what could be more natural? For a similar but more detailed treatment, read Thomas Alexander’s 1980 article on the development of the Mormon doctrine.
Finally, consider even the stock testimony meeting claim, “I know the Church is true,” and Holmes’ working definition of truth, quoted above: “When I say that a thing is true, I mean that I cannot help believing it. I am stating an experience as to which there is no choice.” The standard LDS belief claim makes perfect sense under the definition that Holmes gives. Under this approach to what constitutes a truth claim, what people are saying is that after all that they have read, prayed, and experienced, they cannot help believing the Church is what it claims to be.
So if the life of the Church has not been logic or theology but experience, maybe we’re on the right track. Even Holmes the cynic might have agreed with that claim.
I pulled all of the Holmes quotes from selections in Pragmatism: A Reader (Vintage Books, 1997), edited by Louis Menand.
 from Lecture 1 of The Common Law.
 from “Natural Law,” Harvard Law Review 32 (1918):40-44.
 from “Ideals and Doubts,” Illinois Law Review 10 (1915):1-4.
 from “Natural Law.”
[5, 6] from “The Path of the Law,” Harvard Law Review 10 (1897):457-78 (where it was originally titled “Law and the Study of Law”).