Do Humans Have a Reliable Conscience?

Matthew Braddock
Sunday 19 June 2022
  1. Introduction
  2. Fields of Study
  3. Discussion
  4. Conclusion

1. Introduction

Do humans have a reliable conscience? Do we have generally reliable (though fallible) moral intuitions?

The concept of a conscience refers primarily to our capacity or disposition to make intuitive moral judgments (e.g. about the actions we have done or are planning to do). The question is not whether we humans have a conscience. We clearly do. Rather, the question is whether we have a reliable conscience that we can generally trust to tell us the moral truth. Many believe that we can trust our conscience or moral intuitions. However, this idea is hard to reconcile with two broad scientific findings.

First, consider the extensive moral diversity documented in the scientific literature. The moral differences we find across cultures and history should make us wonder whether we humans really do have a reliable conscience.

Second, consider the influential role of culture. The scientific literature tells us that cultural processes largely determine the specific content of our moral norms and intuitions: though our cognitive dispositions bias us in certain directions, cultural processes largely fill in the details. But this raises a problem. Cultural processes seem highly contingent: they can easily lead humans to all sorts of moral intuitions, including nasty ones. For instance, cultural processes have led humans to moral norms and intuitions permitting homicide, slavery, family abuse, animal cruelty, and so on. If culture largely determines the content of moral intuitions and could have easily led us to intuitions mostly contrary to our own (as moral diversity suggests), then why should we trust our current moral intuitions to be on track? Why should we trust our culturally shaped conscience? Elsewhere I have argued that secular “moral objectivists” or “moral realists” have no good explanation (Braddock 2016; 2021). That is, if there is no God, then we have no good explanation for why highly contingent cultural processes would lead us humans to mostly true intuitions. Secular moral objectivists are forced to postulate an astonishing coincidence between our culturally shaped intuitions and the objective moral truths.

Now the question that seizes me is this: can we explain the general reliability of our moral intuitions theologically, in a way that accommodates the scientific findings of moral diversity and the role of culture? Can theology’s doctrine of conscience succeed where secular moral philosophy has failed?  That is my puzzle.

2. Fields of Study

My puzzle resides at the intersection of moral theology and moral psychology.

2.1 Moral Theology

Moral theology investigates the moral implications of God’s revelation, for example in Scripture. Here is one thing Scripture tells us: God has endowed humans with a basic awareness of objective moral truths, i.e. an imperfect but reliable enough conscience. For example, in the New Testament the apostle Paul claims that God has endowed humans (both Jews and Gentiles) with a moral law “written on their hearts”:

For when Gentiles, who do not have the law [i.e. the commandments given to the Jews], by nature do what the law requires, they are a law to themselves, even though they do not have the law. They show that the work of the law is written on their hearts, while their conscience also bears witness, and their conflicting thoughts accuse or even excuse them on that day when, according to my gospel, God judges the secrets of men by Christ Jesus. (Rom. 2:14-16 ESV)

 The idea that humans have a reliable conscience has a long theological and philosophical history. Medieval theologians and philosophers (e.g. Thomas Aquinas) discussed various conceptions of conscience and “synderesis” (Langston 2001). Modern moral sense theorists and moral intuitionists (e.g. the Earl of Shaftesbury, Thomas Reid, and G. E. Moore) developed similar ideas. However, the doctrine of conscience has received scant attention in recent theology and philosophy of religion (for exceptions, see Evans 2013 and Cottingham 2015). And the attention it does receive is typically not empirically engaged.

What is the doctrine of conscience? Minimally, the doctrine claims that humans have a conscience and that it is reliable. What more does it claim (or should it claim)? Philosopher Thomas E. Hill, Jr. offers us a nice starting point in his description of the “popular religious conception of conscience”, namely “conscience as God-given instinctual access to moral truth”:

  1. Each human being is born with a latent conscience, which (barring certain tragic interferences) emerges into its full working capacity in youth or young adulthood. It is a capacity to identify…acts, motives, intentions, and aims, those that are morally wrong and those that are permissible (i.e., not wrong). …
  2. That certain acts, such as murder and adultery, are morally wrong is a matter of objective fact, independent of our consciences. …
  3. In acknowledging the wrongness of an act, our conscience …. imposes painful feelings of self-disapproval when it recognizes the wrongs of our past or ongoing activities, and it threatens the same when we entertain future plans that it would condemn.
  4. Conscience originates as God’s gift to human beings, a special access to moral truth that can work independently of church authority and rational reflection. …
  5. Appealing to conscience is not the same as using rational, reflective judgment to resolve moral questions. Conscience may be partly shaped and informed by such judgments, as well as by public debates, religious education, and the like, but it is pictured as operating not so much like an intellectual moral adviser as like an instinct-governed, internal “voice” or sign that “tells” us what we must or must not do, warns us when tempted, and prods us to reform when guilty. (Hill 1998, 17-18)

As this popular religious conception and the biblical testimony (Rom. 2:14-16) suggest, one core claim of the doctrine of conscience is the following “intuitionist” claim: humans have the capacity to intuitively know many objective moral truths, and this capacity is grounded in our God-given human nature (Evans 2013, 41-42). More precisely, with proper nurture and education humans with normally functioning cognition will acquire the capacity to intuitively know many objective moral truths. Consider a child drowning in a shallow pond. We intuitively know that it would be right to rescue the child and wrong to drown the child. We usually don’t reason to such particular moral truths but discern them directly. We also intuitively know many general moral truths or principles: other considerations being equal, we should keep our promises, tell the truth, not harm innocent people, help our family and friends in need, and so on. The doctrine of conscience understands this intuitive capacity to be a source of general moral revelation to humans, including those without access to specific revelation like Scripture, tradition, or church teaching.

Qualifications are necessary, of course. Consider three qualifications.

First, the doctrine of conscience implies the general reliability of our moral intuitions, not their infallibility. We know that some (perhaps many) of our moral intuitions are false (e.g. due to cultural influences, motivational bias, etc.), even if we don’t know which ones. But the fact that our moral intuitions are sometimes false does not show that they are generally unreliable.

Second, the claim that humans have this intuitive capacity is compatible with recognizing the vital roles that nurture and education play in its development or frustration (Evans 2013, 42-43). Would a boy raised by wolves intuitively know that he should tell the truth, if he were never culturally exposed to the idea? Presumably not. Some cultural input is necessary. Would a boy raised by thieves inevitably come to believe that thievery is wrong? No. The development of our intuitive capacity can be restricted (or enhanced) by cultural influences, which helps to explain moral diversity.

Third, the claim that we have this intuitive capacity is neutral regarding how it operates and how (or where) it is physically realized in the brain. For instance, it does not entail that there is some distinct faculty or module or part of the brain that realizes this capacity, though it does not rule out such a claim either (Evans 2013, 170-172).

The doctrine of conscience can be supported on theological grounds. First, it can be supported on Scriptural grounds (e.g. Rom. 2:14-16). Second, it can be shown to cohere with other theological doctrines. For example, consider the doctrine of sin: the Christian tradition tells us that humans—including those without access to specific revelation (e.g. Scripture)—are morally responsible for their wrongdoing and need God’s forgiveness. But how could we be responsible for our wrongdoing if we do not generally know the difference between right and wrong? The idea that we have a reliable conscience coheres with the doctrine of sin and other doctrines.

The doctrine of conscience can also be motivated on philosophical grounds. Given theism, should we expect God to ensure that humans have a generally reliable conscience? It seems so. If God is morally good and loving and has created and sustained everything, including humans with their cognitive and moral capacities, then we should not be surprised to find ourselves with a basic moral awareness. For such awareness is necessary for great goods, such as the acquisition of moral virtue and loving friendship with God and other people. A good and loving God would desire such goods for us, just as a father desires such goods for his children. Accordingly, we should not be surprised if God grants us the basic moral awareness necessary to acquire such goods (Braddock 2021, 191). But how (through what means) would God give us this awareness? The idea that God would reveal moral truth only through special revelation (e.g. Scripture) is implausible. For humans without access to special revelation would lack moral awareness. Thus, we can expect God to reveal moral truth through general means, such as through our natural intuitive capacity.

2.2 Moral Psychology

Moral Psychology addresses the sources and content of our moral norms and judgments. The doctrine of conscience seems hard to reconcile with two broad findings of moral psychology.

First, consider moral diversity. The moral psychology and cultural anthropology literature emphasizes extensive moral diversity across cultures and history (Henrich et. al. 2004; Prinz 2007). If the doctrine of conscience were true—if humans really did have generally reliable moral intuitions grounded in a shared human nature—then we would expect a substantial amount of convergence in our moral intuitions. But the empirical literature emphasizes diversity, which seems to disconfirm the doctrine of conscience. Call it the problem of moral diversity.

Second, consider the influential role of culture. The empirical literature tells us that cultural processes largely determine the specific content of our moral norms and intuitions: though our cognitive dispositions bias us in certain directions, cultural processes largely fill in the details (Sripada 2008; Levy and Levy 2020). Even the most prominent nativist models in moral psychology— including moral foundations theory (Haidt 2012) and moral grammar models (Mikhail 2011)—allow that cultural processes play the main difference-making role. But the fact that culture determines the specific content of our moral intuitions raises a problem for the doctrine of conscience. For cultural processes seem highly contingent: they can easily lead humans to all sorts of moral intuitions, including nasty ones. If culture largely determines the content of moral intuitions and could have easily led us to intuitions mostly contrary to our own (as moral diversity suggests), then why should we trust our current moral intuitions to be on track? Why should we trust our culturally shaped conscience? Call it the problem of cultural contingency (Braddock 2021).

3. Discussion

Can the doctrine of conscience address the problems of moral diversity and cultural contingency?

First, consider the problem of moral diversity. The doctrine of conscience would lead us to expect a substantial amount of convergence in our moral intuitions. But the moral psychology literature emphasizes diversity and thus appears to disconfirm the doctrine.

However, a growing body of empirical literature is documenting evidence of moral convergence across cultures and thus providing a needed corrective to the previously lop-sided emphasis on moral diversity. Consider three examples from this literature.

First, Barrett et al. (2016) and Fessler et al. (2015) elicited the moral intuitions of people from eight small-scale traditional societies and two Western societies and discovered widespread agreement that certain types of actions (e.g. intentional harm, wife battery, cheating, defamation, and perjury) are morally wrong. John Mikhail observes that “the studies by Barrett, Fessler, and their colleagues provide powerful evidence that at least some actions elicit universal condemnation, even among non-WEIRD populations…and that these ‘complex, instinctive, and worldwide moral intuitions’…conform to well-established legal rules” (Mikhail 2022, 378).

Second, anthropologist Oliver Curry and his research team at Oxford recently provided evidence of widespread agreement regarding basic moral values. They examined ethnographic data from 60 representative societies and found that specific types of cooperative behavior—such as helping kin, helping the group, reciprocating, being brave, deferring to superiors, dividing disputed resources, and respecting prior possession—were considered morally good (e.g. ethical, virtuous, etc.) by all societies (Curry 2016; Curry et al. 2019).

Third, Mikhail has documented various sorts of empirical evidence for universal moral intuitions and norms (Mikhail 2011; 2022). For instance, consider evidence from comparative law. Mikhail examined hundreds of jurisdictions around the world and found that they all criminalize homicide and accept the relevance of intention in their definition of illegal homicide. In addition, he found that jurisdictions only recognized eight justifications or excuses for homicide ( self-defense, necessity, insanity, duress, provocation, intoxication, mistake of fact, and mistake of law): “this finding suggests that the circumstances in which intentional killing is held to be justified or excused are more constrained than many observers have assumed” (Mikhail 2022, 377).

To be sure, there is moral diversity, but there is mounting evidence that its extent has been previously exaggerated. Moreover, some moral diversity is due to disagreement about non-moral facts. For instance, when two cultures disagree about who it is permissible to kill, they often agree about the moral principle that it is wrong to intentionally kill innocent people—they just disagree about who qualifies as an innocent person. Beneath the surface of moral diversity we often find convergence upon moral principles.

All this suggests that there is a substantial amount of moral convergence which mitigates the problem of moral diversity. Moreover, much of this convergence is plausibly explained by our innate cognitive structures (Mikhail 2022), which confirms the doctrine’s claim that our intuitive moral awareness is somehow grounded in human nature.

Second, consider the problem of cultural contingency. Why should we trust our moral intuitions when the cultural processes shaping them could have easily led us to contrary intuitions?  This is where the doctrine of conscience has an advantage over secular philosophical attempts to explain the reliability of our moral intuitions. If God not only designed our innate cognitive structures but also constrains the direction of human cultures, then we can explain why our culturally shaped intuitions are mostly on track. If God is guiding cultural history for his purposes and desires that humans possess moral awareness, then cultural processes are not highly contingent. C. Stephen Evans makes a similar suggestion regarding the evolutionary process: “If we suppose that the evolutionary process has been guided by God, who has as one of his goals the creation of morally significant human creatures capable of enjoying a relation with God, then it would not seem at all accidental or even unlikely that God would ensure that humans have value beliefs that are largely correct” (Evans 2018).

Of course, questions remain for the doctrine of conscience. For example, why does God permit so much moral error and ignorance? One standard response is that God endowed humans with morally significant freedom, which enables us to form our characters and make significant choices with consequences for ourselves and others. Accordingly, we should not be surprised to find humans making false moral judgments as a result of motivational bias, self-deception, willful moral ignorance, moral blindness due to bad character, the “noetic effects of sin”, and other moral epistemological defects described by moral psychology and theological sources (a locus classicus is Rom. 1:18-32). Of course, moral error can also be non-culpable (e.g. the result of cultural indoctrination), and a good God would presumably not hold humans accountable for such ignorance.

4. Conclusion

Do humans have a reliable conscience? Do we have generally reliable moral intuitions? The idea seems hard to reconcile with what the sciences are telling us about moral diversity and the influential role of culture. However, our discussion suggests that theology’s doctrine of conscience can accommodate these findings. The doctrine coheres with the empirical literature. It also explains the reliability of our moral intuitions and thus succeeds where secular moral philosophy has failed. For these reasons, it deserves more attention.


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Cite this article

Braddock, Matthew. 2022. “Do Humans Have a Reliable Conscience?” Theological Puzzles (Issue 9).

Contact the author

Matthew Braddock
Email: [email protected]

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