To start off this chapter, Baggett and Walls give a set of scenarios. Suppose you look at a clock tower at 2 o'clock and form the belief that it is 2 o'clock. The first scenario is the discursive knowledge case. The clock is accurate and fully functional in this case. Given this, one seems to have justification and (inferential) knowledge. The second scenario is the nondiscursive knowledge scenario. While the clock is accurate and fully functional, one does not infer the time from such factors. Rather, having glanced at the clock, you simply find yourself believing it's 2 o'clock. Or you intuitively know the time accurately without even looking at the clock (though this seems farfetched for us in the actual world). The point here is that this is something more intuitive and perhaps even properly basic, which counts as knowledge.
The third case is a Gettier case. Suppose that the clock broke 24 hours before. It is just a coincidence that you look at the clock at 2 o'clock. Here Baggett and Walls distinguish between objective justification and subjective justification. Objectively speaking, one lacks justification because one is relying on a defective clock. However, one has subjective justification because one has no reason to suspect that the clock is broken and has good reason to believe that it is 2 o'clock. However, one presumably lacks knowledge in this case. The last scenario is the random time scenario. Suppose that the clock was never made to give accurate times, but instead its hands are guided by a random set of electronic signals. So the clock gives the time it does because of causes which are completely disconnected from the actual time. Suppose it gives the time 7:15 when you know well that it is early afternoon. Here there is no knowledge and no justification to think that the time indicated is accurate.
While some may think that naturalism rules out moral knowledge, it does not mean that naturalists lack moral knowledge. For them (and everyone else) to lack moral knowledge, it must be that naturalism rules out moral knowledge and that naturalism is true. However, Baggett and Walls want to maintain that naturalists have moral knowledge.
They start by discussing discursive moral knowledge. Consider three categories of people. The first have argued that on naturalism, both morality and logic lose their validity. Some examples are C. S. Lewis, Victor Reppert and Alvin Plantinga.
The second, such as J. L. Mackie, Richard Joyce, E. O. Wilson, and Michael Ruse, argue that on naturalism, theoretical reasoning retains its power and validity, but normative moral categories are lost.
The last category of people think that reason (and logic) is reliable, and so we should think that morality should be thought of as reliable too. Such are moral realists like Derek Parfit, Erik Wielenberg, David Brink, and David Enoch.
For example, they may say that we are committed to the existence of other norms of reasoning with the same ontological and epistemological properties as moral ones. Angus Ritchie (a theist) argues that there are true statements which (1) are both descriptive of entities and are also prescriptive to those rational agents who come to know their truth, and (2) they are neither analytic nor knowable by empirical research alone. Ritchie identifies norms of theory choice in the physical sciences. Some call these epistemic norms. Ritchie uses inference to the best explanation (IBE) as an example. Physicists routinely make such inferences. The principle is both descriptive and normative, for it tells us what we ought to accept on the basis of evidence generated by empirical observation and experimentation.
Hence based on IBEs, we are committed to the existence of synthetic a priori imperatives. David Enoch takes another approach by arguing that human beings can't help but engage in explanatory projects in order to make sense of the world. Since the practice of explanation is indispensable, and principles of IBE are indispensable to that practice, we have to take their deliverances seriously. Ritchie further conjoins this with the practice of reflective equilibrium where we take singular intuitively compelling judgments and systematize them into general rules.
Next Baggett and Walls discuss nondiscursive moral knowledge. Psychologists distinguish between the "adaptive unconscious," whose operations are fast, automatic, and effortless, and the operations of the conscious mind, which are slow and require work. The former is known as System 1 and the latter as System 2. Some knowledge is nondiscursive. Some, like Plantinga, have argued that certain beliefs are rational, justified, and warranted without being evidentially supported by other propositions because they are properly basic. Baggett and Walls suggest that it is reasonable to think that certain foundational, axiomatic moral convictions might qualify as properly basic beliefs.
Baggett and Walls next discuss moral Gettier cases. Angus Menuge says that the shared claimed of variants of evolutionary ethics (EE) is that the moral sense of human beings is the result of their natural history, which is contingent and could have been different. He makes a distinction where weak EE says that it is only our moral psychology (our moral beliefs) that would be different if we had evolved differently, while strong EE says that moral ontology itself (what actually is right or wrong) would be different if we evolved differently.
Strong EE's main problem is that it makes human rights contingent. It cannot account for moral values and obligations well. Furthermore, Menuge points out that if rights are based on our natural capacities, then some individuals who suffer physical or mental defects do not have rights. Another point is that natural selection may explain what is good for an organism, in that certain characteristics can increase the likelihood of survival and reproduction. Yet the fact that X is good for Y does not imply that X is morally good.
Weak EE on the other hand gives us no grounds for thinking that we could know moral reality. On weak EE, it seems that one is right just by mere coincidence, since our epistemic moral faculties are not properly connected to moral truth. Erik Wielenberg replies that it is a mistake to assume that humans could have evolved with radically different moral principles from the ones we actually possess. While he admits some luck is involved, he does not think it is significant since the same luck afflicts many of our nonmoral beliefs also.
Baggett and Walls now discuss the challenge to justified moral beliefs. If moral beliefs are not dependent on the relevant moral truth-makers, then a tracking relation has not been established to show that our moral judgments essentially depend on actual moral truth. Gilbert Harman, for example, says that if moral beliefs can be given an evolutionary explanation, then they can be explained without appealing to their truth, and thus moral beliefs lack justification. Many others such as Guy Kahane, Michael Ruse, Richard Joyce, Sharon Street, and Mark Linville have advanced similar evolutionary debunking arguments.
Street, for example, assumes that our moral beliefs are fitness-aimed but asks if they are also truth-aimed. If there is no fitness-truth relation, then we should be skeptical about morality. If there is a fitness-truth relation, then it is either that moral beliefs have reproductive fitness because they are true (the tracking relation) or simply because of the fitness they have conferred (the adaptive link account). The adaptive link account leads to constructivism. The moral realist needs a tracking account but this seems implausible. A tracking account of paternal instincts, for example, has to say that such instincts were favored not just because such behavior preserved DNA, but also because it is independently true that parents ought to care for their offspring. Richard Joyce thinks similarly, yet thinks that there is wisdom in a fictionalist approach to ethics, acting as if there are binding moral truths for the purpose of social harmony.
How do secularists respond to the challenge? Baggett and Walls first consider replies by secular naturalists who take moral properties to be natural properties. They examine the Cornell realist account advanced by Boyd, Brink, and Sturgeon. Sturgeon replies to Harman by saying that moral facts are explanatorily relevant. Sturgeon thinks that moral facts are commonly and plausibly thought to have explanatory relevance since many moral explanations appear to be good explanations. Consider the case of Hitler. Harman thinks that we should not think that, over and above such natural facts about Hitler as his anti-semitism and will to power, there is a moral fact of Hitler's depravity. Sturgeon follows Kripke in suggesting that moral terms rigidly designate natural properties, so moral terms pick out natural properties and track them. Justice, for example, picks out some properties such as equity displayed in the distribution of societal goods. This, however, seems to embrace weak EE which seems saddled with an intractable epistemic challenge.
Baggett and Walls then consider instead secular accounts which take moral properties to be non-natural properties (which supervene on natural properties). Neither David Enoch nor Erik Wielenberg provides a tracking account and, and both concede that our moral judgments are not likely directly caused by the relevant moral truths. Instead, they endorse a "third factor" explanation. If we can explain why (1) x causes y, and (2) x entails z, then we have explained why y and z go together.
For example, on one view in philosophy of mind, brain state B causes action A, and B entails mental state M (M supervenes on B), therefore we can explain why M and A go together. Enoch says that this is a (Godless) pre-established-harmony type of explanation. Enoch's solution assumes that survival or reproductive success is at least somewhat good generally. Next he says that evolutionary selective forces have shaped our normative judgments and beliefs with the aim of survival or reproductive success. So the fact that survival is good pre-establishes the harmony between the normative truths and our normative beliefs. While Baggett and Walls think that Enoch's approach has potential, they point out that other worldviews can also affirm the value of human beings and their survival, and arguably better.
Wielenberg's approach is similar but identifies a different third factor. His third factor is certain cognitive faculties. He says that relevant cognitive faculties entail the presence of moral rights and generate beliefs about such rights. How do those faculties entail moral rights? Briefly, he thinks that in light of our cognitive faculties that recognize overriding normative reasons to act, rights are thereby entailed. The primary reservation Baggett and Walls have regarding Wielenberg's account is ontological. They think his account does not do justice to the authority of morality, and does not satisfactory explain the existence of binding moral obligations and human rights.
To support the claim that theism better explains our moral knowledge than secular accounts, Baggett and Walls look to Ritchie. In From Morality to Metaphysics: The Theistic Implications of our Ethical Commitments, Ritchie advances a moral argument for God by accomplishing three central tasks. First he presses the distinction between justification and explanation of moral truths. Second, he engages secular accounts that address moral cognition. Lastly, he defends the theistic alternative. Ritchie asks three questions about the genesis and justification of our cognitive capacities. (1) What is the justification for our faith in their reliability? (2) What is the historical explanation for their development? (3) What is the explanation for their capacity for tracking truth? Ritchie grants the naturalist moral justification and even moral knowledge, but argues that naturalism fails to explain the truth-tracking ability of our moral cognition. He thinks that natural selection can tell a story of how humans come to have truth-tracking capacities for theoretical reasoning, namely, that we will survive better if we hold true beliefs that derive from theoretical reasoning. However, he denies that such correlation is nearly so plausible in the moral case. He thinks that a value system based on survival, replication, and pleasure alone is inadequate. He thinks that there needs to be a wider teleological explanation, one that ultimately involves the intentions of God.
In summary, Baggett and Walls think that (assuming moral realism) moral knowledge is possible. Naturalism faces some challenges from those who Gettierize or challenge naturalists on the issue of moral justification. Instead of arguing that naturalism cannot account for moral knowledge, Baggett and Walls grants moral knowledge but thinks that theism provides a better explanation of our knowledge than naturalism. While they admit that third factor solutions seem to have potential, such solutions are entirely consistent with theism, and in Enoch’s case theism seems to feature better resources to deploy such a solution. So in agreement with Ritchie, they conclude that even if moral knowledge is consistent with naturalism, a better explanation is a theistic one.