Neuroethics and Social Justice

By Neil Levy

Image courtesy of Pixabay
Neuroethics is exciting. It is fascinating to consider the deep issues it raises and the future possibilities it explores. I worry, however, that the focus on the exciting possibilities of present and future neuroscience obscures more pressing ethical issues. These more important issues should count as neuroethical issues.

Neuroethics has been especially concerned with cognitive and affective enhancement. A number of enhancement technologies are either in development or already available, including psychopharmaceuticals like methylphenidate (Elliott et al. 1997; Mehta et al. 2000) and modafinil (Turner et al. 2003), and also transcranial direct current stimulation (Kadosh et al. 2010), to name only the most prominent. Many ethicists are deeply worried about these developments. A range of arguments have been advanced purporting to show that the use of cognitive enhancements is impermissible or at least inadvisable.

Some ethicists have attempted to show that alterations produced by psychopharmaceuticals or electrical stimulation of the brain would be inauthentic (e.g. Elliott 1998). Others have focused not on the traits and capacities produced but on the means whereby they are produced: because these means are technological, they risk mechanizing our self-conceptions (Freedman 1998). Yet others have worried that cognitive enhancement might constitute cheating (Schermer 2008). Perhaps most pervasively, ethicists have worried about the social justice implications of cognitive enhancement (Sandel 2009); cognitive enhancement may well prove expensive, limiting access to those who are better off than average. Even if they are relatively cheap, they will almost certainly be out of reach of the roughly 10% of the world’s population living on less than US$2 a day, adjusted for purchasing power (World Bank 2015). Given that these enhancements are likely to be much more available to those who are already better off, they are likely to increase inequality, within and between countries.

Iodine pills. Image courtesy to Mr. Granger,
Wikimedia Commons
The arguments against cognitive enhancements share a common flaw: they apply equally to a range of existing and relatively uncontroversial means of ensuring that people have desirable traits and capacities. One can run precisely the same arguments, it seems, against such uncontroversial interventions as adding iodine to food. Iodine deficiency remains a significant cause of intellectual disability in developing countries, but it has been largely eliminated in the developed world thanks to the addition of iodine to table salt (UNICEF 2018). Adding iodine to food to enhance mental capacities does not seem different, in principle, to using methylphenidate or modafinil to the same end. There seems no reason to think that the capacities resulting from iodine supplementation would be any more authentic, the means whereby they are produced any less mechanical, the results any fairer or any less unequally distributed, than capacities produced by psychopharmaceuticals.

Faced with the apparent similarities between uses of cognitive enhancers and cases like iodine supplementation, ethicists have sought to identify relevant differences between the two kinds of cases that would explain and justify differential responses to them. Such responses directly or indirectly turn on two major issues: the distinction between treatment and enhancement, and how natural the intervention is.

The treatment/enhancement distinction rests on distinguishing between states of human beings that fall within the normal range and those that are deficits compared to normal functioning. Roughly, treatments aim to raise people to normal functioning, whereas enhancements aim to raise them above that standard. Many ethicists believe that treatments have a different moral status to enhancements: they are, at minimum, morally more urgent than enhancements (e.g. Daniels 2000). This distinction might be invoked to argue why supplementation with iodine is a morally permissible or even required treatment, while using modafinil or methylphenidate, when not medically indicated, is a morally impermissible enhancement.

Image courtesy of Pixabay
Along with others, I doubt the treatment-enhancement distinction is defensible. Even if it is, however, it cannot be invoked to justify distinguishing between supplementation with iodine and the use of psychopharmaceuticals. Though the prevention intellectual disability is very plausibly a treatment and not an enhancement, effect sizes in many studies of iodine supplementation are much less dramatic: while the average benefit is 12 IQ points overall, boosts of just 4 IQ points for children in some areas where iodine levels were already close to sufficient are commonly seen (Zimmerman 2009). Similarly, supplementation with folic acid improves average function (Durga et al. 2007) in a way that cannot reasonably be regarded as a treatment and yet is uncontroversial. No one would argue for the banning of such supplementation, nor against the use of lifestyle interventions like exercise and regular intellectual stimulation to slow normal age-related decline in cognitive capacities. The second way of distinguishing impermissible enhancements from these permissible interventions is with regard to how natural they are. Whereas folate and iodine occur in nature and were ingested by our ancestors, methylphenidate and modafinil are not present in the environment. This fact might explain why use of the former is unproblematic but not of the latter. However, the natural/artificial distinction, even if it can be drawn defensibly, fails to distinguish between interventions that raise cognitive capacities in ways that are intuitively unproblematic and cognitive enhancers. Consider the Flynn effect, the worldwide rise in average IQs. The explanation of the Flynn effect remains controversial, but on most plausible hypotheses, the effect is due to differences between our ancestral environment and the environment in which we currently live. One possibility is the effect is the result of better and longer education. Flynn himself has suggested that it is the richer and more complex environments characteristic of modern societies that explains the effect (Dickens & Flynn 2002). Regardless, it is the differences between our contemporary and our ancestral environments that explain differences in cognitive capacity.

Image courtesy of Toby Hudson, Wikimedia Commons
The failure to find a criterion to justify distinguishing between permissible ways of boosting cognitive capacities and cognitive enhancements has been cited by some ethicists as a reason to promote cognitive enhancement. If you accept that enriched environments, supplementation with folic acid, and so on, are permissible and perhaps even obligatory, it appears that you ought to think that the use of newer cognitive enhancers is permissible too. Logical consistency requires that we accept both or neither. However, I argue that consistency demands more of us than complacency regarding the status quo in the distribution of cognitive enhancers. Rather, I suggest that effects on inequality and social justice, though they cannot justify limiting access to cognitive enhancements, should motivate concerns about existing practices.

I am sympathetic to the concern that cognitive enhancements risk increasing existing inequalities. However, I believe that this worry should motivate concern about existing inequalities, not just future possibilities. Environmental enrichment, for instance, is already unequally distributed, and causes predictable differences in cognitive capacity. Contemporary neuroscience is accumulating evidence that even within developed counties, socioeconomic status causes differences in intelligence and cognitive control (Noble, McCandliss & Farah 2007; Hackman, Farah & Meaney 2010). Much of these differences are due to differences in parenting and in the amount of stimulation given to infants (Farah et al. 2008). Nutrition is likely also to play an important role. Even excluding genuine malnutrition, birth-weight, which reflects the nutritional and health status of the mother, is correlated with IQ (Matte et al. 2001). The factors which cause and predict better cognitive capacity, from education to access to books and stimulating environment, better food and less stress, are today unequally distributed within countries. Across countries, the disparities are even starker.

I suggest that the lack of relevant differences between controversial cognitive enhancers and generally accepted environmental interventions ought to motivate a concern with the latter. Consistency requires that we extend our concern to the uneven distribution of the resources that explain, in significant part, why cognitive capacity is predicted by socioeconomic status. If neuroethics is concerned with the ethical issues of how we manipulate our cognitive capacities, at least in part, we can call the broader issue a neuroethical one. It is, I suggest, by far the most urgent neuroethical issue confronting us today. Far more attention should be paid to it, even if that comes at the expense of superficially more exciting problems concerning psychopharmaceuticals.

Insofar as neuroethicists are concerned with the distribution of cognitive capacities, they are and ought to be concerned with social injustice in a broad sense. Poverty, relative and absolute, explains the unequal distribution of cognitive capacities in the world today. It is a far more pressing neuroethical concern than worries about new technologies or new drugs. It is one that ought to motivate all medical professionals, and especially those involved in the frontline provision of medical services.


Neil Levy is professor of philosophy at Macquarie University and a Senior Research Fellow at the Oxford Uehiro Centre for Practical Ethics. He recently stepped down after 10 years as the editor of the journal Neuroethics.

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Levy, N. (2019). Neuroethics and Social Justice. The Neuroethics Blog. Retrieved on , from


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