This book offers a philosophy for error-prone humans trying to understand messy systems in the real world.

Described by the philosopher A.J. Ayer as a work of 'great originality and power', this book revolutionized contemporary thinking on science and knowledge. Ideas such as the now legendary doctrine of 'falsificationism' electrified the scientific community, influencing even working scientists, as well as post-war philosophy. This astonishing work ranks alongside The Open Society and Its Enemies as one of Popper's most enduring books and contains insights and arguments that demand to be read to this day.

Species concepts for bacteria and other microbes are contentious, because they are often asexual. There is a Problem of Homogeneity: every mutation in an asexual lineage forms a new strain, of which all descendents are clones until a new mutation occurs. We should expect that asexual organisms would form a smear or continuum. What causes the internal homogeneity of asexual lineages, if they are in fact homogeneous? Is there a natural “species concept” for “microbes”? Two main concepts devised for metazoans (...) and metaphytes have been applied to bacteria. One is the Recombination Concept, a revised form of the Biological Species Concept in which the homogenizing mechanism is the sharing of genome fragments, somewhat akin to sexual recombination. The other is the Ecological Species Concept, in which the ecological niche is that which maintains lineages as cohesive. In this paper I will discuss these two concepts, and offer an underlying model that conjoins them, and consider the implications for species concepts in general. In short, my argument is that asexual species are instances of the most primitive and underived notion of species, which I will call “quasispecies”, following Eigen, and that sexual species are merely one derived kind of species. Moreover, I will argue that there is a continuum of recombination from simple viral models in which each strain is a clone, through to obligate recombination of 50% of the parents’ genome, and that consequently there is no sharp division between “microbial” and more familiar species. (shrink)

Biology above the level of the individual organism ? population ecology and genetics, community ecology, biogeography and evolution ? requires the study of intrinsically complex systems. But the dominant philosophies of western science have proven to be inadequate for the study of complexity:(1)The reductionist myth of simplicity leads its advocates to isolate parts as completely as possible and study these parts. It underestimates the importance of interactions in theory, and its recommendations for practice (in agricultural programs or conservation and environmental (...) protection) are typically thwarted by the power of indirect and unanticipated causes rather than by error in the detailed description of their own objects of study.(2)Reductionism ignores properties of complex wholes; the effects of these properties are therefore seen only as noise; this randomness is elevated into an ontological principle which leads to the blocking of investigation and the reification of statistics, so that data reduction and statistical prediction often pass for explanation.(3)The faith in the atomistic nature of the world makes the allocation of relative weights to separate causes the main object of science, and makes it more difficult to study the nature of interconnectedness. (shrink)

Philosophical discussions of species have focused on multicellular, sexual animals and have often neglected to consider unicellular organisms like bacteria. This article begins to fill this gap by considering what species concepts, if any, apply neatly to the bacterial world. First, I argue that the biological species concept cannot be applied to bacteria because of the variable rates of genetic transfer between populations, depending in part on which gene type is prioritized. Second, I present a critique of phylogenetic bacterial species, (...) arguing that phylogenetic bacterial classification requires a questionable metaphysical commitment to the existence of essential genes. I conclude by considering how microbiologists have dealt with these biological complexities by using more pragmatic and not exclusively evolutionary accounts of species. I argue that this pragmatism is not borne of laziness but rather of the substantial conceptual problems in classifying bacteria based on any evolutionary standard. (shrink)

The use of multiple means of determination to “triangulate” on the existence and character of a common phenomenon, object, or result has had a long tradition in science but has seldom been a matter of primary focus. As with many traditions, it is traceable to Aristotle, who valued having multiple explanations of a phenomenon, and it may also be involved in his distinction between special objects of sense and common sensibles. It is implicit though not emphasized in the distinction between (...) primary and secondary qualities from Galileo onward. It is arguably one of several conceptions involved in Whewell’s method of the “consilience of inductions” (Laudan 1971) and is to be found in several places in Peirce. (From M. Brewer and B. Collins, eds., (1981); Scientific Inquiry in the Social Sciences (a festschrift for Donald T. Campbell), San Francisco: Jossey-Bass, pp. 123–162.). (shrink)

As the international genomic research community moves from the tool-making efforts of the Human Genome Project into biomedical applications of those tools, new metaphors are being suggested as useful to understanding how our genes work – and for understanding who we are as biological organisms. In this essay we focus on the Human Microbiome Project as one such translational initiative. The HMP is a new ‘metagenomic’ research effort to sequence the genomes of human microbiological flora, in order to pursue the (...) interesting hypothesis that our ‘microbiome’ plays a vital and interactive role with our human genome in normal human physiology. Rather than describing the human genome as the ‘blueprint’ for human nature, the promoters of the HMP stress the ways in which our primate lineage DNA is interdependent with the genomes of our microbiological flora. They argue that the human body should be understood as an ecosystem with multiple ecological niches and habitats in which a variety of cellular species collaborate and compete, and that human beings should be understood as ‘superorganisms’ that incorporate multiple symbiotic cell species into a single individual with very blurry boundaries. These metaphors carry interesting philosophical messages, but their inspiration is not entirely ideological. Instead, part of their cachet within genome science stems from the ways in which they are rooted in genomic research techniques, in what philosophers of science have called a ‘tools-to-theory’ heuristic. Their emergence within genome science illustrates the complexity of conceptual change in translational research, by showing how it reflects both aspirational and methodological influences. (shrink)

As the international genomic research community moves from the tool-making efforts of the Human Genome Project into biomedical applications of those tools, new metaphors are being suggested as useful to understanding how our genes work - and for understanding who we are as biological organisms. In this essay we focus on the Human Microbiome Project as one such translational initiative. The HMP is a new 'metagenomic' research effort to sequence the genomes of human microbiological flora, in order to pursue the (...) interesting hypothesis that our 'microbiome' plays a vital and interactive role with our human genome in normal human physiology. Rather than describing the human genome as the 'blueprint' for human nature, the promoters of the HMP stress the ways in which our primate lineage DNA is interdependent with the genomes of our microbiological flora. They argue that the human body should be understood as an ecosystem with multiple ecological niches and habitats in which a variety of cellular species collaborate and compete, and that human beings should be understood as 'superorganisms' that incorporate multiple symbiotic cell species into a single individual with very blurry boundaries. These metaphors carry interesting philosophical messages, but their inspiration is not entirely ideological. Instead, part of their cachet within genome science stems from the ways in which they are rooted in genomic research techniques, in what philosophers of science have called a 'tools-to-theory' heuristic. Their emergence within genome science illustrates the complexity of conceptual change in translational research, by showing how it reflects both aspirational and methodological influences. (shrink)

Examines the history and inherent flaws of the tests science has used to measure intelligence.

The ArgumentScientific tools—measurement and calculation instruments, techniques of inference—straddle the line between the context of discovery and the context of justification. In discovery, new scientific tools suggest new theoretical metaphors and concepts; and in justification, these tool-derived theoretical metaphors and concepts are morelikely to be accepted by the scientific community if the tools are already entrenched in scientific practice.Techniques of statistical inference and hypothesis testing entered American psychology first as tools in the 1940s and 1950s and then as cognitive theories (...) in the 1960s and 1970s. Not only did psychologists resists statistical metaphors of mind prior to the institutionalization of inference techniques in their own practice; the cognitive theories they ultimately developed about “the mind as intuitive statistician” still bear the telltale marks of the practical laboratory context in which the tool was used. (shrink)

Calls for the “translation” of research from bench to bedside are increasingly demanding. What is translation, and why does it matter? We sketch the recent history of outcome-oriented translational research in the United States, with a particular focus on the Roadmap Initiative of the National Institutes of Health (Bethesda, MD). Our main example of contemporary translational research is stem cell research, which has superseded genomics as the translational object of choice. We explore the nature of and obstacles to translational research (...) and assess the ethical and biomedical challenges of embracing a translational ethos. (shrink)