[요약] Linquist, S. (2016), "The Conceptual Critique of Innateness"

Linquist, S. (2016), "The Conceptual Critique of Innateness", Philosophy Compass 

1. Introduction

It is widely recognized that the innate versus acquired distinction is a false dichotomy.

• "Interactionist consensus" (Kitcher 2001): every trait results from an interaction between genetic and environmental factors.
• Despite the interactionist consensus, talk of innateness remains commonplace in both academic and colloquial settings.

Eliminativists recommend abolishing the category of innateness from scientific discourse.

• Classifying a trait as innate encourages researchers to neglect environmental influences on its development.
• The concept of innateness lumps together a number of biological properties that ought to be treated as distinct (Bateson 1991; Griffiths 2002; Mameli & Bateson 2006, 2011).
• The concept is associated with a discredited folk biological theory of essentialism (Griffiths, Machery & Linquist 2009; Linquist, Machery, Griffiths & Stotz 2011).

Revisionists maintain that with some tweaking the concept of innateness can be rendered scientifically useful.

• Ariew proposed to define innateness in terms of the biological property of environmental canalization (being developmentally buffered against some normal range of environmental changes).
• Samuels proposed that the innate versus learned distinction marks the boundary between biological and psychological modes of explanation: innateness functions as an explanatory primitive for cognitive science.

2. Why Eliminate "Innate"?

Why would it take a contribution from philosophy to decide whether scientists should jettison innateness from their stock of theoretical terms?

• Innateness is not exclusively a scientific term. It is partly a philosophical challenge to explicate the vernacular or folk concept of innateness (Machery 2017).
• Scientists themselves disagree about whether innateness is a useful construct.

Critiques of Innateness

• Lehrman (1953)'s critique of innateness of some traits which turned out to undergo prenatal conditioning.
• Bateson (1985, 1991; Bateson & Martin 1999)'s observation that at least six meanings are attached to the term "innateness": present at birth; a behavioral difference caused by a genetic difference; adapted over the course of evolution; unchanging throughout development; shared by all members of a species; and not learned). This encourages researchers to unreflectively jump from one property to another.
• Bateson and Mameli (2006, 2007, 2011) identify a total of twenty-six candidate definitions of innateness, many of which are deemed unsatisfactory because they appeal to unclear, unexplained, or controversial notions such as 'genetic information,' 'learning,' 'developmental induction,' and 'normal development.' Other candidates are rejected because they fail to pick out any trait whatsoever (e.g., strictly speaking, no trait is genetically determined). Other candidates apply to all possible traits (e.g., every trait is to some degree genetically influenced or insensitive to the environment). Bateson and Mameli arrive at a shortlist of just eight candidates ('i-properties' as they call them).

Bateson and Mameli's list of i-properties:

• The question is whether one of these properties or some combination provides a useful scientific definition of innateness.
• A solution: stipulation one or more of the i-properties as the referent of "innate."
• Practical problem: the vernacular concept of innateness recognizes several different i-properties as individually sufficient for innateness (Griffiths et al. 2009). A narrow definition would place it in tension with the folk concept.
• Another solution: defining innateness as the cluster of these properties.
• Problem: theoretical reasons for suspecting that the overlap among i-properties is only partial.
• Various mechanisms can explain how certain i-properties are maintained, often in the absence of other i-properties.
• The clutter hypothesis: the presence of any one i-property does not reliably increase the likelihood that a trait will possess another.

Why do some researchers cling to innateness in the face of mounting theoretical opposition and a lack of empirical support? Griffiths (2002) offers sophisticated answers.

• Psychological evidence that most people operate with a fundamentally flawed conception of the biological world (Atran, Medin, & Ross 2002). According to this folk biological picture, organisms can be classified into groupings because they share an inner nature or essence.
• Griffiths (2002) hypothesized that the vernacular concept of innateness is grounded in three particular features that are shared by the essentialist framework:
• Fixity: innate traits are insensitive to environmental influences during development.
• Typicality: innate traits are shared by most adult members of the same species or sex.
• Function: innate traits serve some purpose or end for the organism.
• Griffiths et al. (2009) used a questionnaire survey to test this Three Feature theory: Fixity was enough for subjects to agree that a trait is innate, even without Typicality and Function; Typicality also independently drove innateness judgments; as did Functionality (though to a lesser degree).
• Linquist et al. (2011) expanded the survey to test whether the three features also influence judgments about whether a trait is "in the DNA." They found that "innate" and "in the DNA" draw upon the same underlying folk concept. Researchers in psychology and biology nonetheless employ the folk concept in drawing unjustified inferences among i-properties.
• Knobe and Samuels (2013) report that scientific training had no effect on subjects' judgments about innateness. Both groups relied on the folk concept.
• However, context that encourages subjects to think in a principled way affected the judgments
• The question is whether people who routinely think about innateness tned to engage in the right sort of principled reflection.

3. Innateness as Canalization

Ariew proposes that we should define it more precisely in terms of environmental canalization.

• Ariew observes the concept of innateness is invoked to explain the environmental stability of some trait. Innateness is invoked to explain why a trait develops normally across a certain range of environments.
• Ariew argues that defining innateness in terms of heritability would be a mistake because heritability is highly sensitive to environmental changes.
• Objection against defining innateness in terms of the possession of a "gene for" a given trait: genes are not the sole factors for phenotypes. For example, genetically identical organisms exhibit markedly different phenotypes (Miko 2008).
• An environmentally canalized trait is buffered against certain types and amounts of environmental variation over stages of its development.
• The genetically/environmentally canalized distinction depends on which type of factor was primarily responsible for influencing the "hills" and "valleys".
• A trait should be considered innate to the extent that it is environmentally canalized.
• One advantage of this definition: it represents innateness as a matter of degree rather than as an all-or-nothing property.

Reconstructing Ariew's argument:

1. Primary job criterion: any adequate definition of innateness must be able to explain the environmental stability of a trait across a range of environments.
2. Assumption that canalization is explanatory: Waddington's notion of environmental canalization along with his metaphor of an epigenetic landscape can explain environmental stability.
3. Conclusion: environmental canalization provides an adequate definition of innateness.

Possible senses of "explain" in Ariew's argument:

• First interpretation: innateness provides a proximal causal explanation of developmental stability (objection: below).
• Ariew 1999: canalization explains why developing organisms tend to produce a number of distinct and well-defined body parts despite environmental perturbation.
• Ariew 2007: invariance effect is grounded in a real developmental pathway.
• Second interpretation: innateness provides a unifying explanation of environmental stability (objection: Griffiths & Machery 2008).
• Unifying disparate phenomena under one description.
• For example, three types of birdsong: Upon first encountering the three types of learning, one might assume that they are entirely distinct mechanisms. However, to further discover that they vary along a single parameter, i.e., the "innateness/triggering/acquired" dimension, would seem to unify them in Kitcher's sense.

Problem of the first interpretation:

• It is difficult to see how the landscape metaphor could be regarded as a real causal process. Canalization is a phenomenon to be explained rather than a mechanism that does any explaining.
• At best, Waddington's metaphor provides a useful heuristic for imagining how genetic and environmental factors might interact.
• Gibson and Wagner (2000): Waddington's original notion is an elusive concept that requires clarification.

Problem of the second interpretation:

• Griffiths and Machery (2008): canalization is a multidimensional phenomenon.
• For every trait, there are different types of environmental factors capable of influencing its development, each to varying degrees.
• On this view, whether some trait is classified as relatively innate or acquired depends on which factors a researcher focuses on.
• For example, cowbird's song: insensitive to other male, sensitive to interactions with females. In the case of American sparrow, the opposite is true.

Possible weaker interpretation: heuristic role

• Griffiths and Machery (2008): it is anti-heuristic. The developmental literature abounds with examples of unexpected influences on development (e.g., aggression of adult rats is directly influenced by the posture adopted by their mother while suckling).

4. Innateness as an Explanatory Primitive

Samuels (1998, 2002, 2007) proposes that innate capacities serve as the explanatory primitives for cognitive science.

• On this view, to say that some trait is innate means that cognitive science cannot, in principle, account for its acquisition.
• Innate traits fall under the jurisdiction of some other discipline, such as developmental biology or genetics.
• Cognitive science has, by its nature, a limited set of explanatory resources at its disposal.
• The role of the innate/learned distinction is to mark the cognitive science/biology disciplinary boundary.
• Innate capacities can themselves play an explanatory role in psychology.

Problems

Samuels' anticipation: Some psychological traits that (intuitively) do not qualify as innate are, nonetheless, explainable only in biological terms. For example, one type of cognitive impairment in decision making is caused by damage to the prefrontal cortex.

• Answer: A trait is innate just in case it functions as an explanatory primitive for some correct psychological theory and it is acquired by the organism as a part of its "normal" course of development.
• Mameli and Bateson (2006)'s critique of this appeal to normalcy: Over the evolutionary history of a given trait, indefinitely many environmental factors will have influenced its development. Contemporary environments will resemble ancestral conditions in certain respects and not others.
• Khalidi (2007)'s critique: A complete explanation of this trait would appeal to neurotransmitters in the brain, thus rendering it a form of biological explanation on Samuels' view. The problem is that this trait is sufficiently common to be considered within the normal phenotypic range. However, not all such forms of depression are innate.
• The author's critique: Sharp division among scientific disciplines (Fodor (1974) "Special Sciences") is difficult to reconcile with the way that psychological phenomena are actually explained (Bechtel & Mundale 1999). According to mechanistic model, the explanation of a given psychological phenomenon involves describing the entities and activities that reliably produce it. Those entities and activities are often drawn from both psychology and biology (Bechtel 2008).