This is the second post in a guest series on Catholicism and Conscience from the Markkula Center for Applied Ethics at Santa Clara University. The Markkula center is currently having a yearlong speaker series on Conscience, some of which are of particular interest for Catholic moral theology.  This post is written by  Brian Green, Markkula Center for Applied Ethics, Santa Clara University.

On November 7th, 2013, Francisco Ayala, professor at the University of California, Irvine, came to speak about the compatibility of evolutionary theory and morality. Ayala has published hundreds of articles, many books, and in 1960 was briefly a Dominican priest in Spain before moving to the United States to study evolutionary theory with the great biologist Theodosius Dobzhansky. Ayala is a member of the National Academy of Sciences and a recipient of the Templeton Prize, the National Medal of Science, the Mendel Medal, and many more honors.

Ayala spoke on the topic “Is Biological Evolution Compatible with a Moral Conscience?” His answer, in short, was “yes” – not only are biological evolution and moral conscience compatible, biological evolution is what makes a moral conscience possible. Therefore they are not opposing ideas at all, but rather are deeply connected.

Ayala recounted the course of natural history, from the origin of the universe, through the origin of life, animals, mammals, primates, and finally humans. Within this context he brought up the idea of cultural evolution. While biological evolution relies on the transmission of genes from parents to offspring, and results in gradual morphological change over time, cultural evolution relies on the transmission of ideas between any people, and can produce rapid shifts in culture, such as the widespread adoption of smartphones in just the last decade.

What have biology and culture to do with morality? Biology makes us capable of morality and conscience, Ayala stated, because we can anticipate the consequences of our actions and categorize actions as good and bad – traits we’ve developed thanks to tool-making and language, respectively. Tool-making is something humans have been biologically predisposed to for about 2 million years, and corresponded to a massive threefold increase in brain size. This increased brain size, in turn, corresponded to the growth of intelligence, language, and all the other products of culture, including moral conscience and moral codes.

As social creatures who know our place in a community, we are self-aware and also aware of others.  We have empathy for those we know. Our community has behavioral rules such as “do not kill” which we follow. If we break a rule we feel a sense of wrongness – that we have done what ought not be done. Communities may vary in their moral codes, but all communities of people will have some kinds of moral codes and along with them the sense, in one’s conscience, of having followed the code or not.

Ayala’s comments raised two major questions from the audience. First, if humans had a moral conscience, could non-human animals have moral conscience too? Ayala strongly disagreed with this idea. Non-human animals cannot have a moral conscience because they are not sufficiently self-aware. He rejected studies which seemed to indicate otherwise as “not real science,” and stated that if those studies were true then his laboratory fruit flies were conscious too – which clearly was not meant to elevate fruit flies.

A second question involved how “real” moral norms were. The questioner asked Ayala whether moral norms were real in a Platonic sense, i.e. objective independent of humanity, or whether moral norms were constructs of human culture. Ayala disagreed with these options – there were further options in between the two, which include all the territory within which moral norms are neither arbitrary (as a strict constructionist or moral relativist/nihilist might argue) nor Platonic. Ayala argued for a middle ground where moral norms are informed and constrained by biology. He did not agree with the idea of “moral facts,” but rather argued for “moral dispositions.” He argued that this is not nihilism because the morals are real and related to human biology and evolution.

These last statements are of interest to me because some of my own research is into the metaphysical foundations of Catholic natural law. Some aspects of Ayala’s argument seemed to me reminiscent of Jean Porter’s idea of the “underdetermination” of moral norms by human biology and culture (covered extensively in her book Nature as Reason). To Ayala, our biology predisposes us to certain kinds of needs, which moral codes can then serve. For example, we speak, therefore truth is prized; we need physical products of nature and tools, therefore stealing is not allowed, etc. But the specifics of the codes to protect these and other needs may legitimately vary between cultures. However, Ayala, referencing Darwin, clearly allowed that some forms of morality may be better than others.

Overall, Francisco Ayala presented a strong defense of the compatibility between moral conscience and evolution, and raised other interesting issues on the nature of morality and moral norms. For a morality which takes human nature seriously, as I believe Catholic morality does, the sciences of human nature are also worth taking seriously, and Ayala presented one approach for how science and morality can interact with each other.