The second dimension of Kantian moral faith is the issue of moral rationality. Is morality a fully rational enterprise? An important part of answering that question calls for an inquiry into the matter of whether a commitment to the right and good conduces to our deepest joy and fulfillment. If it doesn’t, then morality might seem to end up being less than a fully rational enterprise, somewhat rationally unstable in key respects.
Morality and Rationality
Morality exhibits a peculiar feature. Often personal happiness and the dictates of morality are consonant, running in the same direction. Personal and universal happiness, in such cases, are not at all at odds, but resonate and harmonize with one another. But what about those cases when doing the right thing might involve sacrifice of personal happiness, perhaps even sacrifice of one’s life? In such situations, if this life is all there is, to give up one’s life is to give up prospects for any further happiness or fulfillment. It’s the end of the line.
In such situations of conflict between personal and universal happiness, between what’s best for oneself and what’s best for others, there seems to emerge a potential tension between morality and rationality. Henry Sidgwick, in his classic Methods of Ethics, recognized this looming disconnect. He thought it may well be perfectly rational to sacrifice oneself in such a situation, but he also thought it would be no less rational to refrain from doing so and instead to privilege one’s own happiness. He called this issue the “dualism of practical reason,” and he attributed the conviction of many that self-sacrifice is rational to “a faith deeply rooted in the moral consciousness of mankind, that there cannot be really and ultimately any conflict between the two kinds of reasonableness.”
On a naturalistic picture of morality and reality, the dualism of practical reason seems inevitable. On those occasions when commitments to personal and universal happiness don’t correspond, we encounter a situation in which the conflict can’t be resolved. Sidgwick admitted that he lacked good reason to think that a complete coincidence of moral duty and self-interest is certain, or even likely. And yet he recognized that our practical reason needs to affirm the connection of virtue and self-interest. Without their ultimate coherence, morality suffers from a rational instability. Sadly, he thought this deeply rooted desire for morality to coincide with self-interest is “doomed to disappointment.”
Such a conspicuous disconnect is no mere failure of desire satisfaction, but a vital need for morality itself to be a fully rational enterprise. Without resolving the dualism of practical reason, the full rationality of morality itself is jeopardized. The classic conflict between self-interest and altruism is a genuine dilemma for naturalists and secular ethicists.
Theistic Therapy
As a secularist himself, Sidgwick ultimately concluded that the problem couldn’t be solved, and that the dualism of practical reason perpetually resides at the heart of morality itself. He did see one potential solution, but he resisted it, namely, a theistic solution. More specifically, he recognized that, if God exists, he could construct sanctions that would “suffice to make it always every one’s interest to promote universal happiness to the best of his knowledge.” His reason for rejecting this solution is that he was convinced that “ethical science can be constructed on an independent basis” and is not “forced to borrow a fundamental and indispensable premise” from theology.
Although he didn’t find this issue to be evidentially significant, perhaps his misgivings were misguided and insufficiently attentive to the evidence. Recall his conviction of the vital need for the dualism of practical reason to be resolved, on pain of the very rational stability of morality, and that there’s evidence of ubiquitous and deep faith in the moral consciousness that there can’t really and ultimately be any conflict between what’s best for oneself and what’s best for others. In the light of these phenomena, what best explains such intuitions? What grounds such faith? If the very rationality of morality is jeopardized by an intractable dualism of practical reason, why can’t it be evidentially significant that the optimal solution is a theistic picture? If it’s reasonable to take morality itself to be an eminently rational enterprise, what noncircular reason can we give to insist that the theistic solution to the dualism of practical reason is precluded from possessing evidential merit?
Particularly if the case has already been made that there are foundational metaphysical and epistemic reasons to take theistic ethics seriously, this new piece of our moral experience and deliberation seems to be another legitimate move in the same direction, another fitting evidential piece to the puzzle. Kant and Plato both recognized that there can’t be a moral demand on us unless reality itself is committed to morality in some deep way. Morality makes sense only if there is a moral demand on the world too, only if reality will in the end satisfy that demand. If we but assume morality makes full rational sense, we’re arguably entitled to see the solution of the dualism of practical reason by theism as evidentially significant.
Rational Stability
This dimension of the moral argument might be called an argument from providence, and its import, when fully laid out, suggests rational warrant for believing in God for the sake of rendering the moral enterprise rationally stable, providing moral motivation able to sustain us in any and all circumstances, and undergirding moral hope rather than despair in light of our inability to ensure the best consequences. We rationally can and morally must hope that, though setting the world right and making justice and peace embrace isn’t our job, it is the solemn, sacred undertaking of Someone, who will be faithful to do it.
And from a Christian perspective, the case is even stronger. If Trinitarian love is primordial reality, we can never advance our true self-interest by selfish behavior, but when we selflessly return love to the God of perfect love, we inevitably promote our own ultimate well-being and highest happiness.