[Topics: Evolutionary Biology, Moral Obligation, Morality]
The Macroevolution of Morals:

On Fundamental Morals from Societal Evolution, and Morality as Both Objective and Not Objective



Charles Darwin Sketch by M.R.P. - MRI Scans of Brain - morality - evolution - James Rachels - C.S. Lewis

Caricature Sketch by M.R.P.
[High-res prints available here]

There is a lot of fascinating scholarship going on in science and philosophy concerning how human morality relates to evolution. Scientists report altruistic behavior in animal communities, and high correlations between specific parts of the brain and moral action; philosophers explore the moral implications of human evolutionmorality - evolution - James Rachels - C.S. Lewis; and both groups do much, much more. Still, the debate is ongoing about whether morality is an objective, universal, literally existing thing or a set of parameters which do not exist in any relevant sense of the word. Much like the compatibilists who illustrate how free will and determinism are not necessarily mutually exclusive, I would like to explore how morality could be both objective and not objective.

The purpose of really good philosophy, and really good philosophical education, is to encourage logical, careful, clear thinking. So, in the interest of at least attempting to do philosophy well, I will try to trace an intuitive explanation of these ideas. Such an explanation, while less scholarly, seems more likely to fuel thought and discussion (much like this instructor teaching Plato with sandwiches) than exhaustive argumentation for the position.

Morality as a Necessary Condition for Communal Existence:

Two of the loudest objections levied against a person who claims that morals evolved in humans are that morality would not be evolutionarily beneficial, and that any account of how morals might be evolutionarily beneficial still fails to provide an explanation for humankind’s apparent sense of moral obligation. Now, that first claim is so demonstrably false that it would hardly need to be refuted (and there is ample information in the first article linked above to refute that claim), but in responding at greater length to that first objection, a response to the second will become clear as well.

In order to see this, one must step back from evolution as the natural selection of individuals by their environment, and look at the emergence of an entire species evolving as a community of individuals. From this perspective, one will be able to observe that although morality, both for the individual and for society, might not be literally objective, this does not mean that it must be purely subjective; it may be functionally objective. Certain basic moral strictures, as twentieth century moral philosopher James Rachels points out, are necessary for a society to go on existing:

Suppose people were free to kill other people at will, and no one thought there was anything wrong with it. In such a “society,” no one could feel secure. Everyone would have to be constantly on guard. People who wanted to survive would have to avoid other people as much as possible. This would inevitably result in individuals trying to become as self-sufficient as possible—after all, associating with others would be dangerous. Society on any large scale would collapse. Of course, people might band together in smaller groups with others that they could trust not to harm them. But notice what this means: they would be forming smaller societies that did acknowledge a rule against murder. The prohibition of murder, then, is a necessary feature of all societies.

There is a general theoretical point here, namely, that there are some moral rules that all societies will have in common, because those rules are necessary for society to exist. (Rachels 157)

One could attempt to imagine such a community of only murderers, or else a society of only dishonest individuals or only thieves, but that society would inevitably self-destruct. For any individual and community of individuals to exist now and to go on existing, they must behave in a way that is conducive to the existence of a society.

Moreover, one can go further than that particular article of Rachels (although his other works, like the one linked above, do deal at length with human evolution) and notice that humans must not only behave in that way, but must be genetically and cognitively hard-wired to feel as though they ought to behave that way. The two go hand-in-hand. Barring coercion, an organism will not commit an action that it does not feel it ought to commit (with the obvious exception of organisms so rudimentary as to have nothing approximating emotion or inclination, who would and do act altruistically with no complications from cognition).

Morality as an Obligation due to Competing Evolutionary Interests:

This notion (that a sense of moral obligation is a part of the hard-wired, evolved structure of cognition that results in moral behavior) is the crucial point missed by the objection of moral realists who insist that moral action does not imply any sense of moral obligation or moral accountability, and that humans would act in their own immediate self-interest above all other considerations as soon as it seems that morality is not objective. As both a necessary condition for communal existence and a literal part of the mind, such drives are inescapable—functionally objective.

An egregious moral wrongdoer would be destined for isolation, and therefore their genetic structure destined for extinction. (Otherwise—if a society consistently failed to identify such wrongdoing—that society would be well on its way to the genetic spread of such traits, and thus the societal self-destruction sketched above.) One could even imagine a sort of mathematically pedantic version of Kant’s categorical imperative, where a person recognizes that any moral wrongdoing on their part makes the statistical likelihood of moral wrongdoing happening to them slightly higher. But that’s a digression; the key here is that this behavior is being enforced by the very structure of the brain, and only to a lesser degree by conscious decision-making. Further, the decision-making process is itself shaped and brought into being by the aforementioned structure.

MRI Scans of Brain - morality - evolution - James Rachels - C.S. Lewis

That exact misunderstanding regarding obligation is everywhere, and underlies C.S. Lewis’ famous discussion of morality in Book 1 of Mere Christianitymorality - evolution - James Rachels - C.S. Lewis when he says that the notion that “feeling a desire to help is quite different from feeling that you ought to help whether you want to or not” (Lewis 9) is a sufficient observation to suppose that there must be multiple sources of such distinct drives—one natural source and one supernatural source, for instance. Most of the errors in this aspect of Lewis’ argument stem from his misunderstandings and apparently superficial experience with evolutionary biology. In this particular case, someone should have recommended that Lewis research humanity’s many unconscious drives (for a brief modern account of this subject, see this paper).

Why, after all, do we perceive moral action as obligatory? Well, humans must experience drives that are a result of being naturally selected for individual survival at the same time as drives that are a result of being naturally selected for group survival. In both cases the source of the drive is the brain, at varying levels of its cognition and control. The navigation and interplay of these mental forces is not at all straightforward or simple; the communal-ethical choice to be taken in any given scenario may possibly reach the level of cognizance as a feeling of desire, a feeling of obligation, both, or neither.


As part of the brain, life-sustaining and fair morality could not possibly be successfully dismissed by the human species. Rachels would have contended that this approach is really just a different way of coming to the conclusion that morality is objective (i.e. not relative), but there is some difficulty to being so absolute with the categories. It is objective, in the sense that it is universal, but it is also not objective, in the sense that it is not the immutable force described by moral realists. This also provides an account of human altruism. Whether an individual’s genes are selected in the communal sense detailed above, or via the individual’s reciprocal self-interest (‘If I scratch your back, you scratch mine’), the result is the same: more individuals inclined toward altruistic behavior.

Functionally objective morality would explain not only human moral inclinations, but also the feeling of moral obligation. Both are necessary aspects of the minds of a community if that community is to have any chance of continuing to exist.

So, that is how morality could be considered both objective and not objective (with only a little bit of quibbling on the word ‘objective’). Now, if you are of the opinion that, whether any of the above is true or not, a non-objective or functionally objective morality is somehow uglier or less desirable than an objective morality, then stay tuned for the next post in this series.

Works Cited:

Lewis, C. S. “Book I. Right and Wrong as a Clue to the Meaning of the Universe.” Mere Christianity. New York: HarperCollins, 1952. 3-33. Print.morality - evolution - James Rachels - C.S. Lewis

Rachels, James. “The Challenge of Cultural Relativism.” Ethics: Essential Readings in Moral Theory. Ed. George Sher. New York: Routledge, 2012. 151-58. Print.morality - evolution - James Rachels - C.S. Lewis

[Topics: Evolutionary Biology, Moral Obligation, Morality]
The Macroevolution of Morals:

On Fundamental Morals from Societal Evolution, and Morality as Both Objective and Not Objective

was last modified: May 12th, 2017 by Daniel Podgorski
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  1. While this certainly is an exciting article that attempts to take on all the biggest names in the smallest space, I believe you jump a few moves in assuming that C.S. Lewis is incorrect. I believe, if you looked into Lewis a little more you would see that he is describe what for you dialectic ally would be to oughts: the ought of desire and the ought of the conscience. And even here we would have to break it down further since many people would describe a desire to follow their conscience while at the sime time feeling a desire to disregard it. This leads an award mind to notice that they currently have an inordinate desire, or a desire in conscious conflict with their highest aim and love. And the inordinate desires to pop up from the subconscious and unconscious, what Christians refer to as the heart.

    • Thank you for taking the time to reply; I truly appreciate it.

      When you say “And the inordinate desires to pop up from the subconscious and unconscious,” it would seem that you agree with me far more than you let on. I am merely pointing out that it is in accord with our best science to observe that “the subconscious and unconscious” are nevertheless relevant portions of an evolved mind.

      Lewis identifies a ‘something you feel you ought to do’ and a ‘something you want to do.’ And I would actually agree that both exist. Yet, armed with a knowledge of our layers of cognitive control, as explained at more length in the linked PMC article, there is no reason to think that the mind can not be the source of conflicting drives. And armed with a sufficient knowledge of evolutionary processes, there is no reason to think that all relevant aspects of the mind would result from anything else.

      It does not matter that they are often in contradiction, as our knowledge of the mind makes it the case that humans not only can experience several different drives at varying levels of cognition, but that we would and do experience drives which are a result of being naturally selected for group survival at the same time as drives which are a result of being naturally selected for individual survival. I would agree that this line of thinking eventually concludes that morality is not objective in most senses of the word, but it nevertheless becomes clear that Lewis is making some pretty large logical leaps when he dismisses outright the idea that the experience of ‘moral obligations’ could be a product of evolutionary processes.

  2. Thank you for the article.

    Regarding the two “loudest” objections:

    I am having trouble understanding how the first linked article helps react to the claim that “human morals are not beneficial from an evolutionary perspective.” It seems to ask more questions than answer them (especially considering the quote from Platt about charities like “Oxfam,” and the concluding quote of Platt’s).

    It is easy to believe a moral obligation like “I should not murder” is beneficial for evolution. Someone claiming that “moral obligations would not be beneficial to evolution” would point to actions like adultery, rape, theft, or to actions done in secret (that would not affect a society’s acceptance of an individual). The variety of moral obligations someone can experience (or contrive for an argument), I think, does not make it so easily demonstrated to be false.

    The Lewis quote you provide does not seem to be contradicted here. Whether stemming from the brain or from somewhere else, of course it is true that the two feelings Lewis described are different. I think he is trying to give an example to help explain his definition of “moral law,” and in that instance is not making a claim about its source.

    Did you intend to say “someone *should* have” recommended Lewis research unconscious drives? (It struck me as ironic.) I’m sure if available he would have researched them; he is certainly not anti-evolution.

    • Thank you for your reply, and for your great questions (on an article I wrote nearly two years ago, no less).

      That first linked article is really only linked as part of the introductory material—being an example of work being done on this and related topics from the scientific side, and nothing more. I never considered it crucial to the case above. But upon re-reading the linked article, I would say that I disagree with some of Platt’s interpretations of the data. I see no reason that humanity’s more extreme sort of altruistic behavior can not be adequately explained by selection for group survival. As I said in my response to a prior comment, “we would and do experience drives which are a result of being naturally selected for group survival at the same time as drives which are a result of being naturally selected for individual survival.” And it is moot for Platt to question the survival-efficacy of the former drives (due to their relative rarity when compared to the latter drives) when you consider the nearly-unparalleled success of humanity as a species.

      When it comes to the quote from Mere Christianity, there is subtext that I apparently assumed readers would possess (a definite mistake on my part—I can’t for the life of me imagine why I would think most or even an appreciable number of readers would already be well-acquainted with the book in question; it was a big seller in its day, but it’s nowhere near as popular anymore). I may later edit the article to make the subtext explicit. That subtext is this: Lewis does not only say that those two types are distinct, but that because they are distinct they therefore have distinct origins. That is the claim I am contradicting.

      I’m not sure, however, how to respond to your point about hidden moral wrongdoing, as my response to that point would more-or-less take the form of the article above. It is a case made in a few steps.

        First, I refer to James Rachels’ account of how the very existence (and ongoing continuation) of a society demands certain moral strictures (therefore their absence among individuals results in literally untenable societies).
        Second, I argue that such ‘moral basics’ are not merely ‘best practices for establishing and maintaining societies,’ but are (due to their nature as being necessary conditions for such societies) evolved aspects of our genetic and cognitive hard-wiring (and thus inescapable).
        Third, I point out that anti-communal moral wrongdoing—being aberrational with respect to the necessary, basic morals for the existence of a society—would only ever be manifest in a small maladapted subset of the population who were destined for extinction (whether because the society identifies the wrongdoing and their genes fail to be passed on, or because their genes succeed in spreading to future generations and eventually the society fails).
        And finally, fourth, I point out that the misunderstanding of conflicting drives within an individual as being wholely distinct (with one resulting from traditionally conceived natural inclinations toward self-interest and one resulting from some theorized external source that is inclined toward group survival) is fairly widespread, surfacing for instance in work by C.S. Lewis.

      That’s all there is to this article. That said, if you want more details about my stance(s), I have since written many more articles on ethics for this series; two that seem directly related are my article about the purported notion that some human morals are universal (including many beyond the ‘functionally objective’ few mentioned above) and my article about contractarian ethics.

      Last, as for your chronological point about directing Lewis to information on unconscious drives . . . yes, I suppose that involves a bit of an anachronism. Haha. When I consider it directly, I must admit that I really don’t know how much was formally known about that topic (and widely available) during the period when Lewis was writing that book. Obviously the PMC article linked in the parenthetical, for instance, did not exist.

      Certainly I did not mean to imply that I was under the impression Lewis was anti-evolution. In an addendum nearby that quoted line (nearby in Mere Christianity, that is), Lewis discusses his impression of evolution for a few paragraphs. As it has now been years since I last read it, I could not tell you his exact reasoning; although I recall feeling that his understanding of the topic was cursory and superficial, I do not recall having any inkling that he was opposed to it generally.

      So really I agree with your comments on most points; I could have been clearer at many junctures in this article. But it was the first article I wrote for this series, and at that time I was sincerely attempting to be brief and non-technical (ambitions I have since largely abandoned). Sorry for any confusion.

      EDIT: Okay, I went ahead and cleaned up the phrasing of the article in a few places. Thanks again for your comment.

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