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Harming animals for research and for food in conditions of moral uncertainty
  1. Robert Streiffer
  1. Medical History and Bioethics, University of Wisconsin-Madison, Madison, Wisconsin, USA
  1. Correspondence to Prof. Robert Streiffer, Medical History and Bioethics, University of Wisconsin-Madison, Madison, WI 53706, USA; rstreiffer{at}

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Koplin and Wilkinson (K&W) argue for the sociological claim that many believe (1) that the moral uncertainty argument provides significant moral reasons against farming human–pig chimaeras for their organs (henceforth, ‘farming for organs’) but (2) that there no are significant moral reasons against farming non-chimeric pigs for food (henceforth, ‘farming for food’). And yet, K&W argue for the ethical claim, that if the moral uncertainty argument provides significant moral reasons against farming for organs then there are similar moral reasons against farming for food.

The moral uncertainty argument appears to be an application of what I have called ‘the moral status framework’ to farming for organs.1–3 According to the moral status framework, human–animal chimaera research should be evaluated as to its risk of (1) enhancing the moral status of an animal to that of a normal human while (2) continuing to treat the animal as animals are usually treated in biomedical research.4 In status-enhancing research, ‘sacrificing the fundamental interests of the chimeric research subject as they would have been sacrificed in any other animal research is the moral equivalent of sacrificing the fundamental interests of a fully functional adult human being. On all but the most extreme animal rights views, this makes status-enhancing research much worse than other biomedical research on animals, and on any plausible view, makes it absolutely unacceptable’.5 K&W similarly say that, according to the moral uncertainty argument, ‘It would be gravely wrong to treat humans the same way we do animal research subjects, or to raise and slaughter humans for their organs. By extension, it would be gravely wrong to use human-pig chimeras in research, or to use them as a source of transplantable organs, if these chimeric animals acquire cognitive capacities that confer human-like moral status’.

Knowing that research meeting conditions (1) and (2) is gravely wrong is only the first part of the ethical evaluation if one is uncertain whether a particular research proposal will meet conditions (1) and (2). As I have argued, ‘The empirical uncertainties regarding the effects that various kinds of xenotransplants would have and the moral uncertainties regarding which effects would be status-enhancing seem to me to be the crux of the practical problems about how to set an acceptable policy’.6 Similarly, K&W argue that ‘The problem is that determining a human-pig chimera’s moral status would be very difficult’.

K&W extend the moral status framework in two interesting ways. First, they articulate a procedure for identifying the acceptable level of uncertainty: consider a practice of generally using organs from non-status-enhanced animals for xenotransplantation (and suppose that practice is ethical), but in X% of cases, when a suitable organ cannot be generated, the organs from a human infant will be harvested. For that practice to be ethical, the value of X must be exceedingly low, perhaps zero. K&W’s proposal is that, for farming for organs to be ethical, it must run no greater chance of being status-enhancing than that exceedingly low value of X.

Although I appreciate the need for discussion about the acceptable level of uncertainty in chimeric research, this procedure does not work. Imagine a large-scale construction project that we can statistically predict will probably cause a serious in injury to one worker. Such a project can still be ethical. Now consider a similar project guaranteed to be accident-free, but which will never be finished unless the workers are highly motivated. And, suppose, that the only way to motivate them is for the supervisor to roll a 100 000-sided die at the end of each day the project is not on schedule and, if he rolls a ‘1’, the supervisor will hit one worker with a lead pipe, causing serious injury. Even if the chance that any worker will be seriously injured is lower in the second case than in the first, it most certainly does not follow that the practice in the second case is ethical.

Second, as indicated by the ethical claim, K&W extend the framework to the farming for food. Although these pigs are not at risk for (1) having their status enhanced and then (2) being treated as animals are usually treated in biomedical research, they are at risk for (3) having a higher moral status than we think they have and (4) being treated as pigs are usually treated in livestock agriculture. As K&W argue, our beliefs about the moral status of non-chimeric pigs are subject to the same kinds of empirical and ethical uncertainties that make us uncertain about whether human–animal chimaera research meets conditions (1) and (2). If the uncertainty about (1) and (2), combined with a suitable principle governing moral uncertainty, provides significant moral reasons against farming for organs, then the uncertainty about (3) and (4), combined with the same principle, provides similar moral reasons against farming for food.

Although this conclusion must be tentative until the suitable principle governing moral uncertainty is identified (K&W concede that the principles they discuss ‘are not the only, nor necessarily the best, approaches one could take’), the ethical claim is plausible and is a useful addition to the food ethics literature discussing the farming for food of organisms whose cognitive capacities have not been conclusively established.7 8

One might quibble about the evidence provided for the sociological claim. K&W begin by citing three commentaries about human–animal chimaeras, but only Savulescu clearly endorses the moral uncertainty argument.9 Marino is concerned about causing the chimeric pigs ‘unbearable suffering,’ but K&W tell us that the moral uncertainty argument is distinct from concerns about animal welfare.10 Knoepfler poses many ‘profoundly challenging questions’ about chimeric research but says little about the answers to those questions and takes no stand on whether our uncertainty about the answers provides significant moral reasons against human–animal chimaera research.11

K&W cite other bioethicists and advisory bodies as endorsing the moral uncertainty argument, but there is variation in how they describe the outcome that should be avoided: is the concern about creating an animal with a humanised brain, with morally relevant cognitive capacities, with highly sophisticated cognitive capacities, with human-like cognitive capacities, with human-like neuronal structures, with human-like consciousness, or with human-like moral status? And is the problem merely the creation of such an individual, the treatment of the individual while alive, the killing of the individual, or some combination of those? K&W presuppose that these are all different expressions of the same argument, but different answers to these questions can result in substantively different conclusions about the range of practices that are morally problematic.

Regardless, K&W’s discussion provides an illuminating parallel between the biomedical research ethics context and the food ethics context, one that I had not noticed despite having a foot in both camps. And I agree that concerns about moral uncertainty provide reasons for concern about farming for food, in addition to the overwhelming reasons already identified in the food ethics and animal ethics literature. Perhaps because the moral uncertainty concerns draw from a different and somewhat novel source, they will find purchase in some who fail to appreciate the force of the other reasons that have been articulated.


Thanks to Paul Kelleher and Josh Mund for their helpful comments.


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  • Contributors I am the sole author.

  • Funding The authors have not declared a specific grant for this research from any funding agency in the public, commercial or not-for-profit sectors.

  • Competing interests None declared.

  • Provenance and peer review Commissioned; internally peer reviewed.

  • Patient consent for publication Not required.

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