The psychological speciesism of humanism

Abstract

Humanists argue for assigning the highest moral status to all humans over any non-humans directly or indirectly on the basis of uniquely superior human cognitive abilities. They may also claim that humanism is the strongest position from which to combat racism, sexism, and other forms of within-species discrimination. I argue that changing conceptual foundations in comparative research and discoveries of advanced cognition in many non-human species reveal humanism’s psychological speciesism and its similarity with common justifications of within-species discrimination.

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Notes

  1. 1.

    While I will use Setiya’s perspicuous label, Bernstein (2017) calls this view “hierarchism”, and Jaworska and Tannenbaum (2018) simply call the humans-only high status “full moral status”. Others define the same position indirectly. Varner (2012) defends a concept of personhood in which individuals with certain cognitive and experiential capacities deserve special respect, and no non-humans have these capacities (though some qualify as near-persons); a parallel label in these terms might be “personism”. In DeGrazia’s terms (1996, 46), given that an ethical theory that did not affirm an equal consideration principle for humans “would yield distinct moral statuses among humans”, humanism is equivalent to affirming equal consideration for humans only. An EC principle (e.g. Singer 1975) holds that one must give equal moral weight to relevantly similar interests of different individuals. This humanism is distinct from secular humanism, “a democratic and ethical life stance” in which humans give meaning to their lives using reason and science, eschewing belief in a supreme supernatural being (https://humanists.international/what-is-humanism/). These humanisms are compatible but logically independent: one can be a moral-status humanist and hold that our higher moral status over animals stems from our greater similarity to God (essentially endorsing the Scala Naturae), and one can be a secular humanist who is a moral-status egalitarian. My discussion is only about moral-status humanism.

  2. 2.

    I use the term “psychological” speciesism, rather than “cognitive” speciesism, because there is significant ongoing debate about what counts as cognitive but no such debate about whether these capacities count as psychological. Perceptual capacities and the so-called moral emotions, such as empathy, are also psychological, but the former have not been recruited to support humanism and the latter (and emotions generally) can be included among the cognitive capacities.

  3. 3.

    Although my discussion is framed mainly in terms of the relative value of lives, my arguments carry over to the relative moral weight of interests or to claims about the rights that humans have that non-humans lack entirely or have to a lesser degree. Whatever the moral category that is the target of concern—lives, rights, or interests—the core idea of humanism is that the human version of that feature has a special moral status or weight greater than that of any non-human versions.

  4. 4.

    The question of consumption of non-human animals is a major issue in animal rights and welfare, but this issue rarely involves a direct conflict between an animal’s life and a human’s life. The difference between humanism and egalitarianism is sharper in conflicts where human lives and livelihoods are at stake.

  5. 5.

    Originally, speciesism was the view that only humans were morally considerable (Gruen 2017). The more common view today (adopted here) is roughly Singer’s (1975, 7): a bias towards the interests of own’s own species and against those of other species, such that similar cases across species are weighed in favor of one’s own species. So defined, speciesism is compatible with affirming that non-humans are morally considerable, but it still violates a universalizability requirement (or equal consideration principle) in moral judgments to treat similar cases similarly. Frequently, the qualifier “illicit” is dropped after first reference, and I’ll generally do so here.

  6. 6.

    For DeGrazia (op.cit.: 58–59), it is “highly arbitrary” to morally distinguish Homo sapiens from our ancestor Homo erectus or to highlight species-level genomic differences rather than genomic differences at other taxonomic levels. For Gruen (op.cit.), the genome is a “a bit of luck that is no more morally interesting than being born in Malaysia or Canada”. I will write that it is arbitrary while leaving open what explains this judgment.

  7. 7.

    For the record, the human genome doesn’t define what it is to be human by contemporary biological definitions of species (e.g. de Queiroz 2007). In general, scientific biological criteria do not yield taxonomies that confirm folk biological categories (Atran 1998).

  8. 8.

    Representative literature reviews include Mather (2019), Suzuki (2016) and Ben Jacob et al. (2004); article collections include Bekoff et al. (2002), Wasserman and Zentall (2012) and Vonk and Shackelford (2012); journal theme issues include those introduced by Vonk and Shackelford (2013) and Heyes (2012). Despite evidence of plant cognition (Trewavas 2016; Gagliano et al. 2016) and arguments for the possibility of plant consciousness (Calvo 2017; Calvo and Keijzer 2011), many philosophers (and scientists) hold that plants are definitely not conscious or cognitive. I set plants aside here, but remain agnostic on this issue.

  9. 9.

    In light of the convention of identifying non-human species by their Latin names in publications, Horner and Whiten’s (op.cit.) title, “Causal knowledge and imitation/emulation switching in chimpanzees (Pan troglodytes) and children (Homo sapiens)” is a sly nod to this perspective. Of course, because we cannot raise humans from birth in controlled laboratory conditions or clone them to eliminate genetic confounds, researchers cannot treat humans and non-humans exactly alike in all ways relevant to interpreting comparative data. These confounds imply some bias in the comparative research record. As it is, the principle that absence of evidence is not evidence of absence may at times be honored in the breach (Pepperberg 2008; Allen and Bekoff 2007, 310).

  10. 10.

    A generalized evolutionary perspective in psychology is distinguished from the specific research programme called Evolutionary Psychology, with upper-case letters often used to mark the difference. The latter (e.g. Barkow et al. 1992) involves specific theoretical commitments, such as to modularity of mind (but see Heyes 2012); one can take an evolutionary perspective on the human mind without endorsing EP. In comparative research, the generalized approach has been labeled comparative evolutionary psychology (Vonk and Shackelford 2012, 2013), defined as the study of evolved traits, and incorporating principles from ethology, ecology, biology, anthropology, and psychology. This includes developmental and social psychology and social sciences as a result of theories emphasizing the role of culture in explaining human cognition (e.g. Heyes 2018; Whiten and Erdal 2012). Much of the new animal cognition research referred to in contemporary philosophical contexts stems from the methodological innovations of the comparative evolutionary psychological framework. Pursuit of research from a more traditional “anthropocentric” approach (Shettleworth 1993, 2009, 2012a, b;  Hulse 2012, 887; Vonk and Shackelford op.cit.) is compatible with the new synthesis, as is any comparative research that backgrounds evolutionary considerations to focus on such problems as the internal mechanisms or ontogenetic development of behavior, or the elucidation of general learning mechanisms. Lyman-Henley and Henley (2000), Parker (2002), Griffiths (2007) and Shettleworth (2012a) provide critical historical accounts of the interrelations between the disciplines that study non-human behavior and cognition and their relations to human cognition and behavior.

  11. 11.

    Even biology has found it difficult to eradicate the idea that evolution progresses from early and simple to late and complex organisms (Gould 1988; Keeling and Burki 2019). Hierarchical thinking can also seep into contemporary neuroscience (Parvizi 2009; Marino 2003).

  12. 12.

    The usual evolutionary processes are natural selection, genetic drift, mutation, and migration (Millstein 2017). While natural selection (adaptation) is considered foremost among these, and thus is a primary source of research questions, comparative evolutionary psychology is not committed to any particular claim about which evolutionary mechanisms explain cognitive traits.

  13. 13.

    Here’s a non-cognitive example. A standard definition of menopause—the age-associated cessation of ovulation prior to death (Walker and Herndon 2008)—is species-neutral. Although it was once thought by some to be a human autapomorphy, killer whales and a few other primates also undergo menopause, each species in its species-specific way (Ward et al. 2009). Thus, menopause might have been uniquely human, but it turned out not to be. Note that a trait that is not a species-level autapomorphy may be an autapomorphy at a higher taxonomic level.

  14. 14.

    This illustration is necessarily highly truncated given the enormous literature on episodic memory across species and ongoing debate regarding its definition and methodologies for studying it. For example, I do not touch on its relationships to other capacities or the potential for acquiring neural evidence (e.g. brain-imaging results) of mental time travel in non-humans.

  15. 15.

    Premack supports a discontinuity view, so for him the difference in degree is so vast as to count as a difference in kind. Whether this will result in a new type (a human cognitive autapomorphy) may depend on other factors, but for present purposes this complication will not matter.

  16. 16.

    Henry Molaison (HM) was left with severe anterograde amnesia following surgery to alleviate epilepsy (Scoville and Milner 1957). He could not form new episodic memories.

  17. 17.

    It is not clear whether his position is intended to be a variety of essentialism about human nature, which is controversial for independent reasons (Kronfeldner et al. 2014). My criticism is independent of this possibility. Anderson (op.cit.: 289) explicitly endorses essentialism about human nature in order to argue that speciesism is not racism – racism (interracial animosity) is a contingent social phenomenon whereas speciesism is not: humans are “by their species nature fit for living with one another in society”.

  18. 18.

    To be clear, my remarks do not reflect any of their views. They also begin their article with a definition of what it is for an entity to have moral status, rather than what moral status is: “An entity has moral status if and only if its interests morally matter to some degree for its own sake.” One might combine these by saying, roughly, that an entity that is not-interferable-with is one whose interests matter. But these can be treated as independent definitions, too.

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Correspondence to Carrie Figdor.

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Figdor, C. The psychological speciesism of humanism. Philos Stud 178, 1545–1569 (2021). https://doi.org/10.1007/s11098-020-01495-y

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Keywords

  • Humanism
  • Speciesism
  • Moral status
  • Marginal cases
  • Comparative psychology
  • Animal cognition
  • Animal welfare
  • Animal rights
  • Evolutionary psychology