Mameli, Matteo - On Innateness: The Clutter Hypothesis and the Cluster Hypothesis

07/03/2009

The Journal of Philosophy, Vol 60 Num 12 Dec 2008

This paper discusses the various problems with specifying what it is for something to be innate and a proposed meta-analysis (Clutter or Cluster) of the concept.

The analysis starts with the 'minimal condition' which is that something that is innate is not learned, and what is learned is not innate. (pg721). Examples of this are Plato's Meno and Chomsky's poverty of stimulus argument about the deep rules of grammar. Author argues that even the minimal condition is too strong since it calls the sex of a particular reptile non-learned (innate) when in actuality it was merely the result of the temperature while being incubated. (pg722) Perhaps, though, 'learning' can be reinterpreted to being a subset of larger 'MAPS', or 'Mechanisms for Adaptive Plasticity', which can be employed without using a psychological process. Under this fix, what is innate is what is not the result of the developmental outcome of a MAP. But author claims this goes awry too because of developmental maladies that aren't acquired through MAPS, but are nonetheless not innate. (pg723)

Author then considers multiple attempts at giving an analysis of innateness. The first is that what is genetically encoded is what is innate (pg724). The difficulty here is that genetic encoding creates things like proteins, not 'whole organism phenotypic traits' like sexual preference, ability to speak a language, obesity. There is a supposed consensus that such traits develop through causal processes that 'involve genetic and non-genetic factors' (pg725). In this way, whole-organism traits cannot be innate, if innate means 'genetically encoded'. The fix here might be to say that for innateness, genes must affect the developmental process relative to the emergence of an innate trait. But author invents a thought experiment that supposedly involves a learned trait that still satisfies this condition. The trait is the ability to understand the theory of Special Relativity-- author argues that this trait is learned but also could be the result of genes that affect the developmental process. (pg725-6) This thought experiment can combat simple genetic encoding analyses and also an account of innateness that specify a certain type of genetic encoding: evolutionary adaptation by natural selection. (pg726-7)

Another possible analysis of innateness is high degree of broad heritability. In this account, high heritability means that variation is mostly due to genetic factors. Author argues that this concept is ill-suited for innateness, since it doesn't have the tools to account for traits like 'having one head' (too universal to count), and it also misses universal traits that are altered by accident, like the trait 'having 10 fingers'. If most of the people without 10 fingers have lost them due to accidents, then the variation is due largely to non-genetic factors, putting the heritability of 'having 10 fingers' on the low end of the scale. (pg728)

The final analysis of innateness is that it involves invariance or canalization, that is, emergence of a trait given most environments-- or a certain degree of developmental 'buffering' against environmental variation. The problem here is that clearly learned traits like 'the belief that water is a liquid' are highly invariable and canalized. (pg729-730)

Author proposes two meta-analyses for the concept of innateness. The first is the Clutter hypothesis, the second is the Cluster hypothesis. The clutter hypothesis is that innateness is a mix of useful concepts that we have just started to pull apart with science, though previously we didn't have the capacity to do so. Therefore the concept is a clutter of different distinct ones and (probably) should be dissolved. (pg730-4) Ironically, author claims that some work has been done that shows that the concept of innatenes 'comes naturally' to humans (pg733). The Cluster hypothesis instead argues that the various aspects of innateness-- canalization, heritability, genetic encoding-- are properties that cluster around a deeper causal process of innateness. In some circumstances we should expect each property of innateness to emerge, but in others, only one property may be present. Those who advocate the cluster analysis will be required to tell the story about this deep causal process, but it is still open as a possibility. (pg735-6) Author claims that it is an empirical question which analysis is true.