Just over a year ago I discovered a philosopher who would come to be one of my favourite thinkers—Nicholas Wolterstorff. As I read his book Justice in Love I was struck by the sharp clarity and rigor of his thought. But what I’ve come to appreciate most about Nicholas Wolterstorff is the gracious manner in which he challenges the views of his opponents. He writes with a Christ-like humility that deserves emulating.
Today I want to share perhaps the most important lesson that I’ve learned from Wolterstorff—that rational people often disagree. Perhaps you already knew that. Let’s take a closer look and see how Wolterstorff understands this common situation.
We need to begin by looking at what Wolterstorff calls Kant-rationality,
A body of philosophical thought possesses Kant-rationality just in case it is based solely on premises and inferences that all cognitively competent adult human beings would accept if those premises and reasons were presented to them, if they understood them, if they possessed the relevant background information, and if they freely reflected on them at sufficient length.
My background is in math and physics. I think that those fields possess Kant-rationality. A mathematical proof is the sort of thing that any competent mathematician would accept if they understood it. If someone rejects a mathematical proof, we think that something is wrong with them. Probably they just don’t understand it, or maybe they’re being stubborn or ignorant.
What about philosophy? Wolterstorff believes that “most philosophers in the modern period have thought that we should aim at Kant-rationality in our practice of philosophy, and that this aim is in principle achievable.” But if this is the case, then what happens when two philosophers disagree (a very, very frequent phenomenon)? If philosophy should indeed aim for Kant-rationality, then if someone disagrees with me it must be “because they’re not cognitively competent, or because they don’t fully understand the issues, or because they haven’t thought about the matter long enough, or because their reflections are in some way not free? All the explanations seem insulting.”
Wolterstorff concludes that, “We must face up to the fact that it’s an illusion to suppose that Kant-rationality is achievable for any substantial body of philosophical thought; over and over it turns out that philosophers who are fully rational find themselves in deep disagreement.” Amen! What he says next has deeply impacted the way I think and deal with intellectual opponents. It is well worth quoting at length.
One enters philosophy as who one is, committed as one is committed, believing what one does believe on matters religious and otherwise; and one participates in the philosophical dialogue taking place. The secular humanist participates as a secular humanist, the Jewish person as Jewish, the secular naturalist as a secular naturalist, the Christian as a Christian. One listens carefully to one’s fellow philosophers who contend that one’s commitments are misguided, one’s beliefs defective, one’s philosophical conclusions mistaken. On some matters, large or small, one finds their arguments cogent; on other matters, large or small, one does not. One then retains the commitments, beliefs, and conclusions one already had, perhaps refined by the fuller’s fire through which they have gone. What else is one to do? One can’t just choose no longer to believe what one did believe. And to those fellow philosophers whose commitments one finds misguided, whose beliefs one finds defective, whose philosophical conclusions one finds mistaken, one offers them arguments to that effect. One hopes they will find those arguments compelling. But one fully expects that often they will not. And so it goes, back and forth. What does one say to the philosopher who has listened carefully to the arguments and counterarguments and remains, or becomes, a convinced secular naturalist? What else can one say but to your deepest commitments and convictions be true as you engage in dialogue with your fellow philosophers on philosophical issues? Be a naturalist philosopher. Show the rest of us where naturalist thinking goes. Perhaps something will turn up that we can appropriate in our own way. And what does one say to the philosopher who has listened carefully to the arguments and counterarguments and remains, or becomes, a convinced Christian? What else can one say but to your deepest commitments and convictions be true as you engage in dialogue with your fellow philosophers on philosophical issues? Be a Christian philosopher. Show those who are of other persuasions where Christian thinking goes. Perhaps something will turn up that they can appropriate in their own way. If the philosophical enterprise, on this way of understanding it, does not aim at Kant-rationality, what does it aim at? It aims at what I shall call dialogic rationality.
Once one realizes that people can rationally disagree, then this also opens the door to doing philosophical theology rationally without needing to first prove that God exists to all skeptics. Those skeptics who understand how to operate using dialogical rationality—rather than grasping at the straws of Kant-rationality—ought to be interested in the project of analytic theology in the same way that I’m interested in how naturalist philosophy explains various topics.
Building my worldview from universally agreed upon first-principles is a fool’s errand since there simply aren’t enough universally agreed upon first principles to do so. Rather,
The analytic philosophical theologian enters the philosophical discussion already holding that God exists and already believing a good many things about God. Whatever it was that led him to believe these things—perhaps revelation, perhaps induction into an ecclesiastical tradition—certainly his convictions are not based ‘solely upon reason’.
 Nicholas Wolterstorff, “Then, Now, and Al,” in Reason, Metaphysics, and Mind: New Essays on the Philosophy of Alvin Plantinga, ed. Kelly James Clark and Michael C Rea (New York, NY: Oxford University Press, 2012), 214 emphasis added.
 Ibid., 215 emphasis added.
 Nicholas Wolterstorff, “How Philosophical Theology Became Possible within the Analytic Tradition of Philosophy,” in Analytic Theology: New Essays in the Philosophy of Theology, ed. Oliver D. Crisp and Michael C. Rea (New York, NY: Oxford University Press, 2009), 167.
Originally posted on Cognitive Resonance.