Red Room Where the Writers Are

    Among the most basic of elements in the representation of concepts is the system of “categories” we all use to make sense of sensory information. Categories are similar to the mathematical concept of “sets” in which elements, perceived or conceived, are assigned to groups which are then manipulated as units in the conceptual process. It is clear that in the evolutionary development of human language, categories preceded language (Bickerton [1] and many others) and are necessary but not sufficient for development of not only of language but also of the more primitive animal call systems, ubiquitous among social animal species. The role of categories in human language has been discussed often by linguists in the last several decades, perhaps most interestingly by George Lakoff in his book about categories and language, Women, Fire, and Dangerous Things [2].

   In 1949 the British philosopher, Gilbert Ryle, published his seminal book, The Concept of Mind [3], in which he discussed some pitfalls in the necessary but tricky use of categories in reasoning. One of the principal goals of Ryle’s book was the destruction of Cartesian dualism as a valid concept in the human understanding of the world, not on the basis of any supposed falsity of “facts” in our conception of “mind” or “soul,” but because the Cartesian treatment represented a logical fallacy which he and others have called a “category mistake.” In the chapter entitled “Descartes’ Myth” Ryle, referring to dualism, said: “It is one big mistake and a mistake of a special kind. It is, namely, a category-mistake. It represents the facts of mental life as if they belonged to one logical type or category (or range of types or categories) when they actually belong to another.” Ryle pointed out that category mistakes are very common in human discourse and are a major source of misunderstanding and conflict.

   In 1735, one hundred and twenty-four years before the publication of Darwin’s On The Origin of Species [4], Carl Linnaeus established a hierarchical system of categories for the classification of all living organisms on earth with the publication of his Systema Naturae [5] It changed the way we think about animals and plants, and it still, in modified form, is used universally by biologists for naming living things. The use of these taxa, particularly the concept of species, enabled Darwin to formulate the concepts addressed in his monumental work. Currently, it’s almost impossible to think about organisms in nature without having every thought heavily informed by issues which have flowed from these two works.

   But the Linnaean taxa are categories defined by humans to help them describe their natural environment. We might ask whether these categories have any reality in nature, or whether they are simply a filing system constructed to help us keep track of observations about our fellow creatures. The higher level taxa are certainly arbitrary, intended to illustrate levels of difference between various groups. Linnaeus himself had no concept of evolution; to the contrary, he believed that species were created by God and therefore eternal. He was simply attempting to put some order into naming conventions that had become very disorderly, and he attempted to do this based on the degree of similarity or difference among the specimens he studied. Evolutionary relationships are now largely regarded as reflecting degree of divergence from a common ancestor, so the two systems of looking at the world, in practice, fit together very well. There is continual shifting around of taxonomic assignment as more information is gathered about groups of organisms. But all taxa are not created equal – one has a definition which is not solely dependent on superficial similarity, and that taxon in the species.

   There are a number of definitions of “species” in use, and often these definitions reflect the underlying philosophies of their users. Some species definitions are, as in higher taxa, based on degree of difference. The most useful definition of species from the standpoint of understanding evolution, at least for sexually reproducing forms, is “a set of actually or potentially interbreeding populations which produce fertile offspring under natural conditions.” This is a useful definition for higher taxa like mammals, birds and fish, but is more problematic for organisms that do not reproduce sexually. Often the question of whether multiple populations or individuals belong to the same species comes down to making the best guess possible with limited biological information. The assignment of species to higher taxa is always to some extent arbitrary and subjective, and there is always some judgment involved about the degree of similarity in such assignments. This is true even as new technologies, such as DNA sequencing, provide other more quantitative points of comparison. But where interbreeding populations of individuals can be established, there is no question about their status. So to the extent we can ever be sure about external realities, species by at least some definitions are, in principle, real; higher taxa are an attempt to show the relationship between species.

   There are often complications to this simplistic account; in many cases, perhaps the majority, data are not available to establish whether two individuals are members of the same potentially interbreeding population. This information is rarely available for extinct species known only from fossils, and there are many contemporary species for which only a few specimens are known, with little information about their variability, geographic range, or ecological niche. For such organisms, species assignment must be based, as it is for higher taxa, on educated guesses based on degree of similarity. Complicating the picture is the large but unknown number of groups of “sibling species,” which are morphologically almost identical, but cannot interbreed, and are in the classical sense, truly different species. Sibling species, of course, could never be detected in fossils. These complications in our ability to reliably identify species, not withstanding, by the standard definition it is clear that species occur in nature, and that we can validly discuss how new ones evolve or have evolved, including the only surviving human species.

   Humans clearly form a single biological species by any common definition, and they are, in terms of biological fitness, the most successful vertebrate organism to have ever lived on this planet. They may turn out to be one of the shortest lived successful species to have ever lived on earth also – this remains to be seen, but we will not live to see it. The key feature that separates humans from all other species is human-style language which not only serves as an effective and flexible means of communication, but also profoundly shapes every aspect of human cognition. For several years I have been exploring what is known, what can be known, about the evolutionary origin of human language, and its role in making us what we are, for better or for worse.

   Speculation and arguments about the origin of human language have been around for several millennia, but they have exploded during the past several decades. It has become clear that a better understanding of language is a key element in having a better understanding of ourselves. Among the many complex behaviors found in higher organisms, human language is unique. Its gigantic lexicon and intricate syntax allow a smooth and infinite linking of concepts that give the human species unprecedented power. At the same time the gestural features and rich texture of language add a powerful engine for social interaction in an already social species. Its very complexity makes understanding its origin difficult and generates a lot of controversy. It prompted Morten Christiansen and Simon Kirby in their book, Language Evolution [6], to ask, “Is this the hardest problem in science?” And the beat goes on. Derek Bickerton has fired the latest shot over the bow of the Chomsky juggernaut with his most recent book, Adam’s Tongue [7], as usual, raising some provocative issues. One thing is abundantly clear. When people speculate about human nature there is an inevitable conflict of interest, and firmly entrenched belief frequently takes over and pushes around any “facts” uncovered. Language origin is inherently an interdisciplinary problem, and when even the most cognizant among us operate outside of our own turf, over simplifications and misinterpretations are the norm. And most importantly among all of the prominent writers in this field, category mistakes, large and small abound. I will be adding posts relating to this general topic in the near future – stay tuned.

[1] Bickerton, Derek, 1990, Language and Species, Chicago, the University of Chicago Press.

[2] George Lakoff, 1987. Women, Fire, and Dangerous Things: What Categories Reveal About the Mind, University of Chicago   Press?

[3] Ryle, Gilbert, 1959, The Concept of Mind, London, Hutchinson & Co.

[4] Darwin, Charles 1859, On the Origin of Species by Means of Natural Selection, or the Preservation of Favoured Races in the Struggle for Life (1st ed.), London, John Murray.

[5] Linnaeus, Carl, 1735, Systema Naturae.

[6] Christiansen, Morten H. and Simon Kirby (Eds), 2003, Language Evolution, New York, Oxford University Press.

[7] Bickerton, Derek, 2009, Adam’s Tongue: How Humans Made Language, How Language Made Humans, New York, Hill and Wang.