I. the origin of species by means of natural selection

Many people have argued that the evolution of the human language faculty cannot be explained by Darwinian natural selection. Chomsky and Gould have suggested that language may have evolved as the by-product of selection for other abilities or as a consequence of as-yet unknown laws of growth and form. Others have argued that a biological specialization for grammar is incompatible with every tenet of Darwinian theory – that it shows no genetic variation, could not exist in any intermediate forms, confers no selective advantage, and would require more evolutionary time and genomic space than is available. We examine these arguments and show that they depend on inaccurate assumptions about biology or language or both. Evolutionary theory offers clear criteria for when a trait should be attributed to natural selection: complex design for some function, and the absence of alternative processes capable of explaining such complexity. Human language meets these criteria: Grammar is a complex mechanism tailored to the transmission of propositional structures through a serial interface. Autonomous and arbitrary grammatical phenomena have been offered as counterexamples to the position that language is an adaptation, but this reasoning is unsound: Communication protocols depend on arbitrary conventions that are adaptive as long as they are shared. Consequently, language acquisition in the child should systematically differ from language evolution in the species, and attempts to analogize them are misleading. Reviewing other arguments and data, we conclude that there is every reason to believe that a specialization for grammar evolved by a conventional neo-Darwinian process.

http://www.biolinguagem.com/ling_cog_cult/pinker_bloom_1990_naturallanguage_naturalselection.pdf

Natural language and natural selection

Language, Thought, and Other Biological Categories

This paper argues that the medical conception of health as absence of disease is a value-free theoretical notion. Its main elements are biological function and statistical normality, in contrast to various other ideas prominent in the literature on health. Apart from universal environmental injuries, diseases are internal states that depress a functional ability below species-typical levels. Health as freedom from disease is then statistical normality of function, i.e., the ability to perform all typical physiological functions with at least typical efficiency. This conception of health is as value-free as statements of biological function. The view that health is essentially value-laden, held by most writers on the topic, seems to have one of two sources: an assumption that health judgments must be practical judgments about the treatment of patients, or a commitment to "positive" health beyond the absence of disease. I suggest that the assumption is mistaken, the commitment possibly misdescribed.

Health as a Theoretical Concept

Although the concept of mental disorder is fundamental to theory and practice in the mental health field, no agreed on and adequate analysis of this concept currently exists. I argue that a disorder is a harmful dysfunction, wherein harmful is a value term based on social norms, and dysfunction is a scientific term referring to the failure of a mental mechanism to perform a natural function for which it was designed by evolution. Thus, the concept of disorder combines value and scientific components. Six other accounts of disorder are evaluated, including the skeptical antipsychiatric view, the value approach, disorder as whatever professionals treat, two scientific approaches (statistical deviance and biological disadvantage), and the operational definition of disorder as "unexpectable distress or disability" in the revised third edition of the Diagnostic and Statistical Manual of Mental Disorders (American Psychiatric Association, 1987). The harmful dysfunction analysis is shown to avoid the problems while preserving the insights of these other approaches.

/pdf/the-concept-of-mental-disorder-on-the-boundary-between-3fi8wf9728.pdf

The concept of mental disorder: On the boundary between biological facts and social values.

In this century a strong tendency has developed to debate social issues in psychiatric 
terms. Whether the topic is criminal responsibility, sexual deviance, feminism, or a host 
of others, claims about mental health are increasingly likely to be the focus of discussion. 
This growing preference for medicine over morals, which might be called the psychiatric 
turn, has an obvious appeal. In the paradigm health discipline, physiological medicine, 
judgments of health and disease are normally uncontroversial. The idea of reaching comparable certainty about difficult ethical problems is an inviting prospect. Unfortunately 
our grasp of the issues that surround the psychiatric turn continues to be impeded, as does 
psychiatric theory itself, by a fundamental misunderstanding of the concept of health. 
With few exceptions, clinicians and philosophers are agreed that health is an essentially 
evaluative notion. According to this consensus view, a value-free science of health is 
impossible. This thesis I believe to be entirely mistaken. I shall argue in this essay that it 
rests on a confusion between the theoretical and the practical senses of "health," or in 
other words, between disease and illness.

On the Distinction between Disease and Illness

Twenty years ago, in four papers,1 I offered a unified descriptive analysis of health, disease, and function. In recent philosophy of medicine, these papers are often treated as a standard defense of one pole on the spectrum of views about health: the extreme view that, at least at the theoretical foundation ofmodern Western medicine, health and disease are value-free scientific concepts. Theoretical health, I argued, is the absence of disease; disease is only statistically species-subnormal biological part-function; therefore, the classification of human states as healthy or diseased is an objective matter, to be read off the biological facts of nature without need of value judgments. Let us refer to this general position as “naturalism”—the opposite of normativism, the view that health judgments are or include value judgments. Following Nordenfelt (1987), let me call my specific naturalist theory the “biostatistical theory (BST),” a name emphasizing that the analysis rests on the concepts of biological function and statistical normality.2

Christopher Boorse

Papers

Health as a Theoretical Concept

On the Distinction between Disease and Illness

A Rebuttal on Health

Wright on functions

What a theory of mental health should be.