The Evolution of Morality: A Skyhook versus Crane Approach

SarahMalayaSniezek's picture

The evolution of morality is one of the most controversial evolutionary topics that has troubled philosophers, biologists, sociologists, and evolutionary psychologists since the inception of natural selection as the major theory of biological evolution. Even Darwin himself had difficulty concretely explaining the origin of morality (Uchii 1996). In sum, the subject’s complexity has generated many conflicting theories, most of which conform to the theory of natural selection, while others use it to undermine Darwin’s original theory of evolution. In this paper, I will first outline some prominent theories of the evolution of morality. I will then analyze the evolution of morality without assuming natural selection is true, and use my analysis to determine if the most logical explanations of the evolution of morality support or contest the theory of natural selection. In doing so I will argue that Dennett’s assertion that “cranes” (theories based on reductionist logic) are more valid theories than “skyhooks” (theories involving mystery of miracle) is detrimental to the evolution of the theory of evolution.

The majority of theories that explain the evolution of morality use Darwinian natural selection as the underlying mechanism that enabled the evolution of morality to occur. In other words, before they analyze the evolution of morality itself, they presume that natural selection is inherently true and use that “fact” to create their theory of the evolution of morality. As stated, these theorists have had some difficulty constructing a theoretically sound argument. This is due to the fact that morality seems to contradict natural selection at the individual level (Dennett 1995; Uchii 1996; Byron 1999). If an individual acts altruistically (putting others welfare above one’s own), then he or she is allocating his or her resources from his or herself to another. This gives those who act selfishly (not altruistically) a selective advantage, because they have more time and energy to spend looking out for their best interest (Dennett 1995; Uchii 1996; Byron 1999). Darwin, and others alike, created the notion of group selection to nullify this disparity. Darwin states that humans are social animals; they live and interact in groups. In this sense, morality would give groups who work together a selective advantage over those who do not (Uchii 1996). An opposition has asserted, however, how morality would be selected within the group to come to a point where an entire group would be able to use it to its advantage (Dennett 1995; Byron 1999). Another theory related to group selection is indirect reciprocal altruism, which supports the evolution of morality through natural selection on a group level. This theory asserts that if conducted correctly, altruism can be naturally selected for on the individual level. While an individual acting altruistically all the time will be less fit than a selfish individual, an individual who acts altruistically only towards those who, in turn, act altruistically towards them will be more fit than a selfish individual (Byron 1999). I feel that this is the less wrong of the two natural selection based theories.

These two theories are what Daniel Dennett (1995) describes as cranes. Cranes are reductionist theories based on natural selection. He believes that only cranes are valid theories, while skyhooks, theories based in mystery or miracle, are invalid (Dennett 1995; Johnson 1995). I feel that Dennett’s classification between cranes and skyhooks, labeling each as valid and invalid respectively, does injustice to the more dynamic theories of the evolution of morality. One such skyhook theory is that morality did not evolve at all. It was merely a “natural malfunction” that was a biological byproduct of the higher order thinking, which was what was actually selected for (Roberts). This theory is in accordance with the notion that natural selection and morality are at odds with one another, but sat the same time, adheres to Darwinism. Another similar skyhook theory that also conforms to Darwinism is the idea that higher intelligence corresponds to higher mental fragility (susceptibility to insanity). It is hypothesized that morality acts as a way to occupy the mind in a fashion that decreases susceptibility to insanity, and because insanity is selectively unfavorable, morality would be naturally selected. An argument against this, however, is that there could be many “tricks” the mind could play other than morality to keep it from going insane, so then why would something as complex as morality, which serves so many other functions, be the one to evolve?

Even greater skyhook’s are theories that do not support natural selection at all, and given the disparity between it and morality, these skyhooks need to be given more admiration. I feel that the best way to approach the evolution of morality is not to start with a theory of biological evolution as a means to generate theory of moral evolution, but instead to start from morality itself; the way Darwin approached biology when creating his theory of natural selection. Therefore, I will begin by assessing the advantages of morality that have not yet been discussed.

An extremely important feature of morality that I have yet to see discussed is the fact that it gives a species a greater ability to protect future generations; not just one generation ahead, but multiple generations ahead. For example, the moral debate about global warming consumes early 21st century life. If we were inherently selfish, we would not care about the issue, because global warming does not directly affect humans beyond what sunscreen can deter. Instead, we are moral; most humans care about hurting the earth to the point where it becomes inhabitable to future generations. This is a unique characteristic that is extremely advantageous to a species under natural selection; however, there is no selective basis for it, because it is a characteristic that does not give individuals, groups, or even societies any contemporary selective advantage. The selective advantage is given generations that do not even exist yet! If natural selection has no premeditative features, then how did this feature of morality come about? If natural selection works as Darwin stated, then this must be the most biologically advantageous byproduct of natural selection ever discovered; possible…yes, probable…no.

Probability, however, is always at odds with the Darwinian notion that life was created through a random process. Mathematicians have calculated the probability of life forming at a random process. They found the likelihood of the smallest theoretical organism created in a random process on any one of 1023 planets to be one in almost three million or about .0003% (Ankerberg and Weldon). Science has adopted an acceptable statistical significance as high as 5% to nullify a process as random; that is over 16,000 times the probability of life forming in the universe.

Probability and morality alike, give reason to believe that evolution is not as simple as Darwin describes. We cannot settle for cranes when there is ample evidence to support the need for skyhooks to better understand the evolution of morality, and consequently, the evolution of species. Does this mean that there must be an intelligent designer whom many believe directs the formation of life…no, but it leaves it as a somewhat valid option. For now, at least, it seems as if emergence gives the best explanation for the evolution of both morality and species. Emergence is the philosophical theory that large complex systems such as life come from simple, disorganized smaller agents through means unpredictable by reductionism or pure logic. These complex systems are unplanned, but emerge from the sum of the actions of disorganized agents, even though, given the nature of the initial agents, these complex systems are unforeseeable. In relation to the evolution of morality, emergence can account for both morality’s anti-selective (individual selfishness increases fitness) and super-selective (ability to help future generations) characteristics that reductionist theory can not. While emergence is likely not the correct explanation for the evolution of morality, it is one that seems less wrong than those previously discussed. Ultimately, as long as we can find logical gaps in any theory we need skyhooks, not cranes to help develop a less wrong understanding of the world behind us, before us, and around us.



Ankerber, John and Weldon, John “The Evolution of Life, Probability Considerations and Common Sense – Part Three” Ankerberg Theological Research Institute. 2006.

Byron, Michael “Evolutionary Ethics and Biologically Supportable Morality"Proceedings of Twentieth World Congress of Philosophy, PAIDEIA: Philosophy Educating Humanity, electronic version published online. May, 1999.

Dennett, Daniel Darwin’s Dangerous Idea: Evolution and the Meanings of Life. Simon
and Schuster, 1995.

Johnson, Phillip E. “Daniel Dennett’s Dangerous Idea” The New Criterion, October, 1995.

Roberts, Phil Jr. “The Autonomy of Reasoning” Unpublished, electronic version
available at Undated.

Uchii, Soshichi “Darwin on the Evolution of Morality” 19th Century Biology,
International Fellows Conference at the University of Pittsburg. May 20 1996.


Anne Dalke's picture

calling for skyhooks



You set this up well, telling me what your project is, and where you plan to arrive by the end of it; I like the signposts! Your claim is that “skyhooks” are necessary (as signposts? place holders?) in order for the story of evolution to continue to evolve. In an interesting revision of Dennett, you argue that “we cannot settle for cranes when there is ample evidence to support the need for skyhooks….”

What I most appreciate in your move, in the center of the paper, to follow Darwin in arguing from the “bottom-up,” from concrete observations, rather than “top-down” (from an over-arching theory). Demonstrating how theory can emerge from the bottom up, rather than being imposed from the top-down, is a very nice set-up for your final move into emergence theory.

You use current concerns about global warming as an example of our altruistic tendencies; not sure that works, since the biological argument of natural selection has to do with preserving the species, not the individual organism. I’m also not quite sure I follow/understand your argument that probability is “always @ odds” with Darwinian randomness.

You frequently say that “you feel” (for example, that one theory is “less wrong” than another. What’s the difference between feeling, belief, argument, knowledge? You need, in a paper like this one, to back up all beliefs with data, evidence, observations, and sometimes those dimensions are missing here. What are your reasons for your beliefs? Give me data! Evidence!


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