Wednesday 9 March 2011

What, if anything does it mean to say that a trait is 'innate'?

[A little more philosophy, a discussion of evolutionary biology and a look at the 'nature vs nurture' argument]

In recent times it has become commonplace to use the term innate to describe certain characteristics of an organism. In this essay I intend to explore what it means to use this word and why it is such an important topic of discussion. A large factor in this debate is the distinction between acquired and innate traits, better known as the nature versus nurture argument. In order to assess what it means to say that a trait is innate, I will look closely as this dichotomy exploring various different scholars with a view to understanding the use of the word innate in a scientific framework as well as the more colloquial context we frequently encounter. I shall then assess the ramifications of what it means when we say a trait is innate, looking at the consequences socially, culturally and morally, in order to understand just how important the term innate can be.
There has been much analysis of the term innate in philosophy during recent times, the main goal of which is to try and define what we mean when we use the word innate. The ideas that I intend to assess are firstly that of Stephen Stich’s concept of innateness as traits that are universal for a species[1]. Secondly I shall analyse the view of innateness as adaptation proposed by Konrad Lorenz[2] and also look at the similar work of Muhammad Ali Khalidi[3]. The third and most influential definition identifies innate traits as those created by patterns of interaction between genes and environment, known as canalisation put forth by Andre Ariew[4]. Furthermore, leading on from the idea of replacing the term innate, I will consider the sceptical tradition in which it is believed that the concept of innate is ultimately meaningless and a distinction between traits that are learned and those which are innate does not exist.
We often see the term innate being described as ‘in the genes’ or ‘in our DNA.’ However, our genes play a fundamental role in the production of every trait, therefore it is not correct to say that innate traits are ‘in the genes’ and traits that are acquired or learned are ‘caused by the environment’. We would expect to see a far more complex relationship between genes and traits then this simplistic view. This view has its origins in 1935 when Konrad Lorenz articulated that the object of ethology was to distinguish behaviours that were learned or acquired from those which are innate. Here we see the beginning of the dichotomy of innate and acquired traits which has since become a very popular school of thought and more importantly very widely misunderstood.
A major problem that has occurred from this separation of innate and acquired traits is that while we have a label and method of classifying learned traits which are traits that are caused by the environment of an organism, such as muscle mass or calluses on hands or paws. However, when we try to label traits we consider to be innate such as the ability to roll your tongue, we find that rather than applying a premise to innate characteristics we are just using the word innate to describe that which we are unable to label as a product of our environment. This crude usage of the term innate is what has made the word so unclear and troublesome for philosophers and scientists.
A large problem with trying to define the word innate is we come across a multitude of definitions. Innate is widely thought to mean present at birth, a product of genes, bound to develop no matter what, difficult or impossible to change, explained by biological evolution, biologically adaptive, typical of the species.[5] Furthermore, Matteo Mameli and Bateson have recently systematically reviewed the scientific use of the term innate and identified no less than twenty-six proposed definitions. They judge eight of these to be both genuinely independent definitions and potentially valuable scientific constructs.[6] This becomes problematic when you consider that there is little correlation between these definitions, which has led many towards the view that the term innate is confusing and unhelpful within a scientific context.
This confusion has lead thinkers such as Paul Griffiths to the view that the term is obsolete within precise science. Griffiths suggested that we should attempt to provide a revised, more precise definition to traits in order to accurately and specifically define the trait in question. As this essay progresses Griffiths view will become clearer when we look at the definitions proposed by other scholars and how they can fit into this way of seeing the problem with the term innate.
One attempt to try and define the term innate comes from the work of Stephen Stich. In his paper ‘The idea of innateness’, he defined an innate trait as a trait an organism will manifest in the normal course of development. For example Huntington Chorea, which is a disease that only appears 20 or more years into a person’s life. However Stich himself offered a counter example to this idea in universally held beliefs such as, that water quenches thirst. By this definition this would count as innate, which seems counter intuitive.[7] I believe that Stich's idea confuses evidence for innateness with innateness itself, which leaves me with the belief that little can be gained from this early attempt to define innateness.
Another effort was taken on by Muhammad Ali Khalidi, who elaborated on the work of Stich and Lorenz. To understand the ideas of Khalidi we must first look at Lorenz’s suggestion that a trait is innate if its development is guided by inherited information rather than environmental information.[8] This idea is similar to Stich’s independent analysis[9] Stich noted, it is important specify what is meant by ‘information’. Lorenz identified ‘information’ in this context with adaptive fit. Quintessentially his ‘inherited information’ analysis amounts to the claim that a trait is innate if its fit to the environment can only be explained by evolutionary adaptation.
Khalidi presents his analysis in terms of the ‘poverty of the stimulus’ argument, an example of this argument can be found in the work of linguist Noam Chomsky and the belief that language is innate.[10] His argument follows that the examples of speech to which children are exposed do not contain enough evidence to settle which remarks are grammatical in the language they are trying to attain. However, children consistently acquire the grammar of their native language. Therefore, Chomsky concluded, children must have innate knowledge about grammar which supplements the evidence to which they are exposed during development. If this argument is sound, every normal childhood is a deprivation experiment that confirms the innateness of grammar. Khalidi’s argument goes on to say that ‘…a belief (concept, idea, capacity) may be considered to be innate to the degree that it would emerge as the result of an impoverished stimulus’[11] He defines impoverishment as ‘informational impoverishment’ which is a gap between the information in the environment which an organism develops and the information manifested in the trait that develops in that environment.[12] However it is important to note that difficulties stand in the way of actually measuring the information content of an environment. Khalidi did suggest however that scientist’s do have a method of assessing the informational gap, using various forms of deprivation experiments.
According to Lorenz, a trait has more ‘information’ than its developmental environment if the functional adjustment of the trait to the environment cannot be explained by the environment. The deprivation experiment is designed to eliminate just those factors that could explain the trait's functional adjustment to the environment. However, a problem with this occurs when we consider the case of innate diseases in relation to Khalidi’s idea of an informational gap between innate traits and the developmental environment. Khalidi believes that innateness ought to apply to disease phenotypes as well as to functional phenotypes.[13] Is the typical developmental environment of a human child ‘informationally impoverished’ compared to the cognitive deficits seen in Down's syndrome? Without the resources presented by the idea of adaptation Khalidi's notion of ‘information’ would fall into a simple notion of covariance, and his investigation of innateness would be a version of the canalisation analysis which is to be discussed in the next section.
Andre Ariew published a series of influential papers (1996, 1999, 2006) which put forth the notion that innateness is canalisation.[14] Canalisation is a theory introduced by the embryologist and theoretical biologist Conrad H. Waddington.[15] Ariew uses canalisation to show the environmental stability of traits, meaning certain traits will develop in a variety of environmental conditions. Ariew illustrates his idea by using Waddington’s experiment on embryo tissues to show that when ectoderm tissues is at the stage at which it can become neural tissue it can be induced by a large variety of different compounds, therefore this appears as if the neural tissue will come into existence without requiring a specific set of environmental conditions.[16] One important aspect of canalisation which poses a potential problem to some, is the fact that Ariew moves away from the dichotomy of innate and acquired traits and suggests that innateness is rather a matter of degree difference that lies along a spectrum with highly canalized development outcomes on the one end and highly environmentally sensitive development outcomes on the other end. The degree to which a trait is innate is the degree to which its developmental outcome is canalized.[17] I believe that moving away from this dichotomy is an important step in understanding traits, while Lorenz’s popular distinction rested on the familiar Darwinian distinction between genes and environments. I feel that despite the best efforts of many scientists little is gained from thinking in this way. Perhaps Ariew is shifting the scientific paradigm away from the old dichotomy towards a new way of looking at the innate and acquired distinction.
Ariew’s method of defining innateness does not directly correlate to the common language usage of the word innate. Rather Ariew is attempting to explain a strategy of research used by scientists like Chomsky. When terms like innate and instinct are used they should be interpreted in a scientific context. Ariew calls this ‘biologicising the mind’[18] This attempt to make the term innate more scientific is one which in my opinion gives it more concrete meaning and a context in which it can be discussed. I feel this is a very important point because of the potential hazards that can arise when the term is misused.
What does it mean to say a trait is innate? What exactly are the potential outcomes of claiming that a certain trait is innate? For example it has become common within today’s society to hear that certain people are innately violent. Using the word innate in this way gives rise to the belief that certain individuals are genetically determined to be this way and in effect takes the blame away from the individual and onto genetics. While it is true that some people do have a predisposition towards aggressive behaviour this does not mean that they will necessarily commit violent acts. It is important to remember in this example that while we are a product of our genes we also have the capability to act in a manner that might contradict our genetic makeup. This example shows just how easily the term innate can be misused and often is. I consider this use of the word innate comparable to an idea of original sin but just for our modern scientific culture. What this point highlights to me is just how easily this problem can be avoided. By using terms with less connotations then innate then we will experience less confusion and false conclusions. For example saying that a person has a tendency to be violent is far less dangerous than saying that a person is innately violent.
This leads me to discuss the sceptical tradition regarding the innate acquired distinction. My point of using other terms to substitute the word innate is supported by Paul Griffiths and Ethologist Patrick Bateson. Bateson urges researchers to “Say what you mean (even if it uses a bit more space) rather than unintentionally confuse your readers by employing a word such as innate that carries so many different connotations”[19] I believe that innate is a word that within our society and culture has, due its widespread usage and multitude of meanings has been transformed into a pseudo-scientific term which carries too many associations for it to be valuable scientifically and colloquially.
In conclusion I believe that the more we have come to learn about genetics and the science of evolution, the more we have come to know that concepts like the innate and acquired traits dichotomy are far too simplistic and can cause dangerous modes of thinking. While I don’t believe that the term should be retired completely, I hold that it no longer has a place in scientific usage as it can be replaced with terms like canalisation which do not carry the same stigma that the term innate does.



[1] Stich, S. P. (1975). “The idea of innateness”, Innate Ideas, S. P. Stich. Los Angeles: University of California Press.
[2] Lorenz, K. Z. (1966). Evolution & the Modification of Behaviour, London: Methuen & Co.
[3] Khalidi, M. A. (2002). “Nature and Nurture in Cognition,” British Journal for the Philosophy of Science
[4] Ariew, A. (1996). “Innateness and Canalization,” Philosophy of Science, 63(3) (Supplement): S19-S27.
[5] Garvey, B. (2007) “Philosophy of Biology”, Acumen Publishing Ltd. p95
[6] Mameli, M. and P. P. G. Bateson (2006). “Innateness and the sciences,” Biology and Philosophy p177
[7] Stich, S. P. (1975).
[8] Lorenz, K. Z. (1966). 
[9] Stich, S. P. (1975). P13-16
[10] Chomsky, N. (1957). Syntactic Structures, The Hague: Morton.
[11] Khalidi, M. A. (2002). p269
[12] Khalidi, M. A. (2007). “Innate cognitive capacities,” Mind & Language, p100
[13] Khalidi, M. A. (2007). p97
[14] Ariew, A. (1999). “Innateness is Canalization: In Defense of a Developmental Account of Innateness,” Where Biology Meets Psychology: Philosophical Essays, V. G. Hardcastle (ed.), Cambridge, MA: MIT Press
[15] Waddington, C. H. (1942). “Canalisation of development and the inheritance of acquired characters,” Nature, 150: 563–565
[16] Garvey, B. (2007) p99
[17] Ariew, A. (1999).
[18] Ariew, A. (2006). Innateness. Handbook of the Philosophy of Science, M. Matthen and C. Stevens (eds.), Amsterdam: Elsevier. 3: 1–18.
[19] Bateson, P. P. G. (1991). “Are there principles of behavioural development?” The Development and Integration of Behaviour: Essays in honour of Robert Hinde, P. P. G. Bateson (ed.), Cambridge: Cambridge University Press. p22

4 comments:

  1. wouw difficult read (not my native tongue :P)

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  2. I have to admit, I skipped to the conclusion eventually, but it was still quite interesting!

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  3. Innate, like almost everything, is simply perception.

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