Animal Disenhancement & Human Enhancement


In this case, a philosophy student and vegetarian contemplates whether animal disenhancement — engineering the cognitive and physical abilities of animals so that they cannot suffer psychological and physical harms — would make factory farming more morally acceptable. He also wonders whether philosophical arguments in favor of animal disenhancement could be extended to support human disenhancement.


Jonathan Jacob Leduc has been a vegetarian for over ten years. While he doesn’t believe that killing animals for food or using animals in scientific research is inherently morally wrong, he prefers to abstain from consuming meat because he objects to the current economic structures which needlessly cause animal suffering in both medical experimentation and industrial livestock and food production.

Many of Jonathan’s friends have asked him whether he would change his position given recent developments in biotechnologies which have the potential to dis-enhance the cognitive and physical abilities of animals so that they cannot suffer psychological and physical harms.

Consider, they claim, researchers who conducted studies on a certain strain of blind chickens and showed that they were less likely to experience distress in crowded conditions. Crowded conditions are the status quo in poultry and egg production in the US, which cause chickens to become aggressive and inflict harm on each other. Blind chickens, however, do not display this stress or behaviour. Thus, one can claim that, if using this strain of blind chickens for egg and poultry production means lessening animal suffering, and increasing overall animal welfare, then the poultry industry ought to do so on moral grounds. [1]

Now, while this particular strain of blind chickens is not the product of bioengineering, it is reasonable to think that, in the near future, we may be tempted to apply methods in which biotechnologies are applied to animals to lessen their ability to feel pain or distress from so-called production diseases in factory farming and do so in a cost-effective way. For example, we may be able to genetically remove or disable the development of certain traits in animals. Or, we may be able to synthetically “build” modified living organisms without central nervous systems that can produce meat, milk, and eggs for our use. Philosophers have considered the possibility of inducing microcephaly in pigs or cows so that we can reduce their ability to suffer from psychological distress resulting from our industrial practices (Clark 1994). 

Jonathan thinks animal disenhancement is a rational response to people’s concerns about animal welfare in factory farming in the context of industrial farming practices. However, the more he thinks about the possibility of applying these technologies to fundamentally change the nature of chickens, pigs, or cattle, the more he feels uneasy about the implications of such interventions. He considers whether lessening animal suffering by genetic interventions is enough to justify the exploitation of animals in these industries. As a philosophy student, Jonathan also considers how the ability to modify cognitive and physical traits in animals could be eventually applied to human beings and, more importantly, how the philosophical arguments to reduce suffering in animals might lead to undesirable outcomes if applied to human beings in the same way.    

Discussion Questions

  1. Jonathan cares about animal welfare and he accepts that applications of these technologies to animals are more likely to bring about less animal suffering than efforts to protest against the methods of production in factory farms. However, he wonders, is that enough to justify their use?
  2. What if disenhancement technologies were to apply to lessen the pain of human beings who suffered from debilitating illnesses or degenerative conditions? What if they were applied to create non-sentient humans who could be used as models in scientific research or for harvesting organs and tissues for our future use? Is there a morally salient difference between these two scenarios? Is one more or less justifiable than the other?
  3. Jonathan is bothered with the assumption that the best we could do is to lessen animal suffering in the contexts of medical research and factory farming, rather than challenge the use of animals within these practices themselves. He thinks that if this example were to be extended to apply to technologies that could potentially make human beings better off in some sense, it is not clear whether such applications would always be morally justified. Might there be cases in which enhancing human traits might ignore some gross injustices inherent in current social and economic arrangements? If so, is that sufficient to claim that we should not try to make humans better off in any way we can?


Balzer, Philipp, Klaus Peter Rippe, and Peter Schaber. "Two concepts of dignity for humans and non-human organisms in the context of genetic engineering." Journal of Agricultural and Environmental Ethics 13, no. 1 (2000): 7-27.

Clark, Stephen RL. "Genetic and other engineering." Journal of applied philosophy 11, no. 2 (1994): 233-237.

De Vries, Rob. "Genetic engineering and the integrity of animals." Journal of Agricultural and Environmental Ethics 19, no. 5 (2006): 469-493.

Heeger, Robert. “Genetic engineering and the dignity of creatures” Journal of Agricultural and Environmental Ethics 13 (2000): 43-51.

Henschke, Adam. "Making sense of animal disenhancement." NanoEthics 6, no. 1 (2012): 55-64.

Kass, Leon. “The Wisdom of Repugnance.” The New Republic. June 2, 1997.

Midgley, Mary. "Biotechnology and monstrosity: why we should pay attention to the “yuk factor”." Hastings Center Report 30, no. 5 (2000): 7-15.

Palmer, Clare. “Animal Disenhancement and the Non-Identity Problem: A Response to Thompson.” Nanoethics 5 (2011): 43-48. 

Regan, Tom. The Case for Animal Rights. Berkeley: University of California Press, 1983.  

Rollin, Bernard. The Frankenstein Syndrome: Ethical and Social Issues in the Genetic Engineering of Animals. Cambridge University Press, 1995.

Schultz-Bergin, Marcus. "Making better sense of animal disenhancement: a reply to Henschke." NanoEthics 8, no. 1 (2014): 101-109.

Singer, Peter. Animal Liberation. Revised Edition. Harper-Collins, 2002.

Thompson, Paul B. "Ethics and the genetic engineering of food animals." Journal of Agricultural and Environmental Ethics 10, no. 1 (1997): 1-23.

Thompson, Paul B. "The opposite of human enhancement: nanotechnology and the blind chicken problem." Nanoethics 2 (2008): 305-316.

  • [1]The ethical dilemma and the example of the blind chickens are found in Thompson (2008).

The author wishes to acknowledge the contributions of Karin Ellison, OEC - Life and Environmental Sciences Editor, and Joseph Herkert, OEC Engineering co-Editor. They provided valuable input in selecting topics and crafting the resources.

This material is based upon work supported by the National Science Foundation under Award No. 1355547, Karin Ellison and Joseph Herkert, Arizona State University sub-award Co-PIs. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation.