Having explained how we approach the natural only over the interval of the supernatural, Hart turns to the incoherency of materialism.
Absolute truth
The human longing for truth involves a loyalty to an ultimate ideal, and that ultimate ideal beckons to us from beyond the totality of beings. We would not care at all about beliefs and persuasions – our own and others’ – were it not for a deeper need to possess the truth. This is an irony for materialists. When they insist that there is no supernatural beyond – and therefore no absolute ideal — they are asserting what they contend is a truth. They implicitly invoke the very ideal whose existence they deny.
any dedication to truth as an absolute or even preeminent value is at best a paradoxical commitment for a person of naturalist bent; and yet such a commitment is at some level inseparable from all rational life. Anyone who sincerely believes that truth ought to be honored, and that the mind should desire to know the truth as a matter of unconditional obligation, thereby assents to a very ancient metaphysical proposition: that the true is also the good.
Absolute good
Just as everyone, including materialists, believes in “truth as such,” (though that is paradoxical for materialists) everyone also believes in “goodness as such;” that is, the absolute ideal of goodness – of morality. But the desire for goodness is even more problematic for materialists than is desire for truth. That is because truth is a concept that stands on its own. A materialist can seek it even while he ignores the implications of the fact that he seeks it.
Not so with ethical matters, however, because ethical choices involve volition. Atheists believe in “goodness as such” and in fact insist that they are as ethical and as moral as theists. But, they have to simultaneously be saying that transcendent ideals such as goodness are illusory.
Evolution and morality
The usual way for materialists to reconcile this difficulty is to invoke what Hart calls “a sort of evolutionary utilitarianism.” This consists of, first, attempting to reduce the human ethical sense to a variety of traits that have been implanted in us by natural selection by virtue of the evolutionary advantages they confer; and second, that those ethical imperatives ought to be accorded real authority.
These two are things are entirely contradictory, however. If we exhibit traits that we collectively regard as ethical because those traits are naturally selected for, then there is no basis for saying we ought to exhibit those traits. They exist, on this theory, in the same way as do physical traits like height or eye color. At the same time, if those traits are authoritative, then they cannot be mere products of evolution. Materialists have to be saying both that: (a) morality is a contingent product of brute, amoral nature, and (b) that morality is binding upon the conscience of rational man. This is a contradiction.
God embodies good
Morality as explained by theists requires no such contradiction. “[T]he good is an eternal reality, a transcendental truth that is ultimately identical with the very essence of God.” God is not merely a superlatively good contingent being, but the ontological substance of goodness. God is good, not only in the sense that He does good, but in the sense that He is goodness itself. He defines goodness and embodies it.
The dilemma in Plato’s Euthyphro: are the commands of the gods good because they are the gods’ commands, or are they the gods’ commands because they are good? This dilemma is thought to present theism with a defeat, but it does not. It is meaningless, if we properly conceive of God. He is not simply someone who is good, but goodness itself. Indeed, that was Plato’s point, in essence. He wrote this inquiry to show that there must be some eternal principle beyond either material nature or limited and willful lesser deities.
Selflessness and selfishness
Materialism not only can’t adequately explain morality, but its premises point against the development of morality. Indeed, “Every act for the sake of the good is a subversion of the logic of materialism.” The logic of materialism dictates selfishness, not selfless acts of good. The substitute offered by materialists, sympathy, (or what Phillip Zuckerman calls “empathetic reciprocity”) does not support an ethical system. Sympathy is a moral emotion only when interpreted in light of a prior existing commitment to moral goodness. Feeling empathy for another person’s situation does not by itself translate to a moral obligation.
Materialism rests upon an essential selfishness, because that is what the theory of natural selection means. That selfishness nonetheless manifests in moral goodness, materialists believe, because of evolutionary necessity. Moral goodness is selected for in human beings, they hold. That logic requires an essential selfishness at bottom, however. Materialism means that there is no such thing as real selflessness, or if there is, it is a selflessness founded upon a more essential selfishness.
This is suspect enough on its face, but especially so when we consider that this way of thinking ignores completely an important element to our motivation to selflessness: that we act as we do all the while thinking that selflessness is a positive good. That is, we don’t just act selflessly, we act with conviction that selflessness is good. That fact, also, is not explained by the evolution model.
Orientation to moral absolutes
It is clear that an orientation to an absolute exists, because even an atheist ascribes absolute moral value, though it may not be a moral value sanctioned by God. In other words, we may disagree about what the moral thing is, but we do not disagree that the moral thing is to do the moral thing.
Take, for example, disagreement about abortion, as a moral issue. A pro-life person of course believes that preserving human life is an absolute moral good, so abortion is wrong. A pro-abortion person believes that personal autonomy is the absolute moral good, and so restriction on it is wrong. But both believe in moral absolutes.
It is the fact of there being a moral absolute at all that undermines the materialist stance. As soon as you posit a moral absolute, you posit an Absolute in which the moral sense abides, and from Whom we inherit it. Evolution cannot explain any moral absolute.
The fact that there is any good in us at all argues against the evolutionary explanation for morality, but suppose that we accept this selfishness-manifested-as-selflessness explanation. There would still be many observable instances of extravagant charity, kindness, generosity, or self-sacrifice, in circumstances in which one can find no benefit for the person engaged in such acts, or their posterity. Even one such act defies the supposed evolutionary imperatives to act selfishly, for self or posterity. It would be inexplicable, if evolutionary explanations for morality were true.