“For good nurture and education implant good constitutions, and these good constitutions taking root in a good education improve more and more, and this improvement affects the breed in man as in other animals” wrote Plato in his Dialogues. And, ever since, the discussion as to what may be learnt and what may be innate has meandered on, often becoming embroiled in passionate debates laced with opposing ideological positions.


In the 19th century the discussion began to be more informed by new scientific findings, but far from resolving the question, positions if anything became more polarized. “Of all the vulgar modes of escaping from the consideration of the social and moral influences on the human mind”, wrote John Stuart Mill in 1848, “the most vulgar is that of attributing the diversities of conduct and character to inherent natural differences”. But in The Descent of Man [1874], Darwin responded that ‘The ignoring of all transmitted mental qualities will, as it seems to me, be hereafter judged as a most serious blemish in the works of Mr. Mill’. Strong words, indeed, from the gentlemanly Darwin.


Darwin’s cousin Francis Galton then introduced the dichotomous language of ‘nature and nurture’ in his English Men of Science: Their Nature and Nurture [1874]. As Galton pointed out ‘the phrase ‘nature and nurture’ is a convenient jingle of words’, useful because ‘it separates under two distinct heads the innumerable elements of which personality is composed’, yet not forgetting to add that ‘no carefulness of nurture can overcome the evil tendencies of an intrinsically bad physique, weak brain, or brutal disposition’. To the present day the ‘nature-nurture’ framing of the discussion has tended to dominate public discourse, despite repeated attempts by biologists to introduce more nuanced understandings of the shaping of human personhood.


The Galtonian phraseology continues to dominate books on the subject. A quick dip in to Amazon reveals titles such as: Nature or Nurture (Dowling, 2004), Nature and Nurture (Keating, 2013), Nature via Nurture (Ridley, 2003), Nurture the Nature (Gurian, 2009), The Nurture of Nature (Wall, 2009), The Nature of Nurture (Wachs, 1992), Nature versus Nurture (Collins, 2002), Nurture by Nature (Tieger and Barbara, 1997), Nurture through Nature (Warden, 2007), and many other similar titles besides. One wonders whether the possible combinations of the two words might by now have reached its limit.


The 20th century saw wild swings between an emphasis on either nature or nurture. Deterministic hereditarian ideas tended to dominate in the earlier decades of the century, only for the pendulum to swing in the direction of a powerful environmental determinism. The Nobel prize-winning Marxist geneticist Hermann Muller [1890-1967] envisaged (in 1935) that through selective breeding, within a century most people could have ‘the innate qualities of such men as Lenin, Newton, Leonardo, Pasteur, Beethoven, Omar Khayyam, Pushkin, Sun Yat Sen, Marx, or even to possess their varied faculties combined’. The aspirations of today’s transhumanists seem mild by comparison.


But in the same era the behavioural psychologists J.B. Watson and B.F. Skinner led the charge against ‘instinctivism’ with Skinner famously declaring that: ‘the nature of human nature is that humans have no nature’. The reaction against deterministic ideas on heredity came too late to counter the eugenic policies of the Third Reich with terrifying consequences. So great was the subsequent revulsion against the abuses of genetics in Hitler’s Germany following the Second World War that hereditarian theories of behavior were treated with suspicion for years and nurture reigned supreme.


The pendulum once more began to swing with the flourishing of molecular biology from the 1960s onwards, then sociobiology in the 1970s, followed by evolutionary psychology and the sequencing of the human genome in the early noughties, described upon its publication by hubristic metaphors such as ‘the Holy Grail’, ‘the Book of Life’ and ‘the Code of Codes’. Today the phrase “it’s in her DNA” or “in the organisation’s DNA” has come to mean characteristics that are stable and unchanging – somewhat missing the point that our DNA is undergoing a constant process of change and diversification.


Today older versions of hereditarian or environmental determinism are thankfully no longer with us, at least in the crude versions so commonly found in the last century. Instead genetic determinism is a more subtle, insidious assumption, absorbed more by a process of cultural osmosis than by overt assertion, a process often aided by the miscommunication of genetic results in the scientific literature. As a recent News Feature in Nature reports: “An increasing number of studies suggest that biology can exert a significant influence on political beliefs and behaviours”, suggesting that “genes could exert a pull on attitudes concerning topics such as abortion, immigration, the death penalty and pacifism”. John Hibbing, a political scientist at the University of Nebraska-Lincoln, is quoted as saying that “…it is difficult to change someone’s mind about political issues because their reactions are rooted in their physiology”. We note the assumption of determinism. Genes and physiology are seen as something different from ‘us’ and ‘our mind’, and they seem to be controlling us, so we can’t even change our mind.


Genes, Determinism and God aims to critically survey the current state-of-play with regard to the role of genes in human personhood, focusing on the relationship between genetic variation and human behaviour in the context of ideas about human freedom and determinism. It is contemporary biology more than ideological considerations which subvert all kinds of dichotomous pairings, be they nature-nurture, hereditary-learning or genes-environment. Developmental biology provides the key and a considerable portion of the book is given over to explaining – for the non-specialist – how human personhood emerges from a lengthy multi-causal developmental process in which the genome is but one important molecular component amongst many.


This leads on to a survey of the underlying methods and assumptions of quantitative human behavioural genetics, before delving into the molecular genetics of human behaviour, followed by a critical survey of the applications of behavioural genetics in the study of intelligence, religion, politics, sexual orientation, and criminality.


Philosophical questions pop up all over the book, particularly relating to the question of genetic causation, a question pertinent to both animal and human behavioural differences. What does it mean to say that a gene causes something? And what exactly does it cause? Such questions become most relevant in a chapter on the philosophy of free will and determinism, where the aim is to map out a framework that enables a rational discussion to be carried out concerning the extent to which genetic variation impinges on both the ontological reality of free will as well as the human experience of choosing freely. The position advocated is expressed via Dual-Aspect Monistic Emergentism [DAME], a bit of a mouthful, but a position drawing on a rich literature on the philosophy of both compatibilism and emergentism.


Theological reflection in the book centres round the ancient Judaeo-Christian idea of humankind made in the image of God, an idea that has been historically powerful, contributing to the shaping of moral values, political systems, medical care, education and the justification of human rights.


Thomas Metzinger has commented in a recent edited volume entitled Neural Correlates of Consciousness: Empirical and Conceptual Questions that ‘Implicit in all these new data on the genetic, evolutionary, or neurocomputational roots of conscious human existence is a radically new understanding of what it means to be human’ – going on to claim that this emerging account of the human person is ‘strictly incompatible with the Christian image of man’. Genes, Determinism and God takes precisely the opposite view: never before have the findings of science regarding the human person seemed so compatible with a Christian understanding of human personhood, and never before so relevant to the bioethical challenges arising from advances in genetics.


Following some discussion of what the term ‘image of God’ actually means in its linguistic context of the Ancient Near East, the concept is then brought into discussion with genetics in five different ways: first, via discussion of the image of God as referring to the whole person, consistent with the integrated view of personhood provided by contemporary developmental biology; second, via the way in which the ‘image of God’ provides a basis for the value and status of each human individual, subverting any attempt to discriminate against people based on their genetic endowment; third, via the question as to how far we should go in controlling or changing the genome; fourth, via the celebration of diversity in community which is nurtured by both genetics and theology; and, fifth, via the way in which being made in the image of God provides a theological underpinning for notions of moral responsibility and free will.


This is a ‘both-and’ book. Those who prefer confrontational ‘either-or’ discourse should look elsewhere.


Denis Alexander is a founding fellow of the ISSR and Emeritus Director of The Faraday Institute for Science and Religion, St. Edmund’s College, Cambridge, where he is Emeritus Fellow. Genes, Determinism and God was published by Cambridge University Press on July 13th 2017, and is based on the author’s Gifford Lectures given at St. Andrews University, Scotland, in 2012. The book is available from the on-line Shop of The Faraday Institute at the discounted price of £17.00 [www.faraday-institute.org].




Genes, Determinism, and God will help readers move away from sensational headlines with their wrongheaded notions about genes and human behavior to a more nuanced, helpful understanding of how human behavior is and is not shaped by genetics. Denis Alexander has done a splendid job of making an incredibly daunting, multidisciplinary subject accessible.”

Jeff Hardin, Professor and Chair, Department of Zoology, University of Wisconsin-Madison, USA


“A fascinating read about free will and much more – including human nature, human behavioral genetics, criminality, politics, and the image of God. Highly readable and instructive.”

Alfred R. Mele, Professor of Philosophy, Florida State University, USA


“In this sophisticated but accessible exploration of the relationship between human genetics and human behavior, the author provides a state-of-the-art survey.  Moving authoritatively from history and biology to philosophy and theology, he explores the evidence for both free will and determinism, touching on such contentious topics as the nature-nurture debate and the heritability of intelligence, homosexuality, and criminality. A real tour de force.”

Ronald L. Numbers, Professor Emeritus of the History of Science and Medicine, University of Wisconsin-Madison, USA