In recent years the notion of biological specificity has attracted significant philosophical attention. This paper focuses on host specificity, a kind of biological specificity that has not yet been discussed by philosophers, and which concerns the extent to which a species is selective in the range of other species it exploits for feeding and/or reproduction. Host specificity is an important notion in ecology, where it plays a variety of theoretical roles. Here I focus on the role of host specificity in (...) biological control, a field of applied ecology that deals with the suppression of pests through the use of living organisms. Examining host specificity and its role in biological control yields several valuable contributions to our understanding of biological specificity. In particular, I argue that host specificity cannot be fully understood in terms of Woodward’s well-known account of causal specificity. To adequately account for host specificity, we need a notion of causal specificity that takes into consideration the extent to which a variable’s effects are similar to one another – a dimension not captured in Woodward’s account. In addition, the literature on host specificity in biological control highlights certain aspects in which causally specific relationships can be practically valuable that have not yet been addressed in philosophical discussions of specificity. That literature also reveals that in certain contexts specificity can hinder rather than foster effective control, thus leading to a nuanced assessment of the practical value of specific causes. (shrink)

The history of developmental biology is interwoven with debates as to whether mechanistic explanations of development are possible or whether alternative explanatory principles or even vital forces need to be assumed. In particular, the demonstrated ability of embryonic cells to tune their developmental fate precisely to their relative position and the overall size of the embryo was once thought to be inexplicable in mechanistic terms. Taking a causal perspective, this Element examines to what extent and how developmental biology, having turned (...) molecular about four decades ago, has been able to meet the vitalist challenge. It focuses not only on the nature of explanations but also on the usefulness of causal knowledge – including the knowledge of classical experimental embryology – for further scientific discovery. It also shows how this causal perspective allows us to understand the nature and significance of some key concepts, including organizer, signal and morphogen. This title is also available as Open Access on Cambridge Core. (shrink)

Human microbiome research makes causal connections between entire microbial communities and a wide array of traits that range from physiological diseases to psychological states. To evaluate these causal claims, we first examine a well-known single-microbe causal explanation: of Helicobacter pylori causing ulcers. This apparently straightforward causal explanation is not so simple, however. It does not achieve a key explanatory standard in microbiology, of Koch’s postulates, which rely on manipulations of single-microorganism cultures to infer causal relationships to disease. When Koch’s postulates (...) are framed by an interventionist causal framework, it is clearer what the H. pylori explanation achieves and where its explanatory strengths lie. After assessing this ‘simple’, single-microbe case, we apply the interventionist framework to two key areas of microbiome research, in which obesity and mental health states are purportedly explained by microbiomes. Despite the experimental data available, interventionist criteria for explanation show that many of the causal claims generated by microbiome research are weak or misleading. We focus on the stability, specificity and proportionality of proposed microbiome causal explanations, and evaluate how effectively these dimensions of causal explanation are achieved in some promising avenues of research. We suggest some conceptual and explanatory strategies to improve how causal claims about microbiomes are made. (shrink)

Several authors have used the notion of causal specificity in order to defend non-parity about genetic causes (Waters 2007, Woodward 2010, Weber 2017, forthcoming). Non-parity in this context is the idea that DNA and some other biomolecules that are often described as information-bearers by biologists play a unique role in life processes, an idea that has been challenged by Developmental Systems Theory (e.g., Oyama 2000). Indeed, it has proven to be quite difficult to state clearly what the alleged special role (...) of genetic causes consists in. In this paper, I show that the set of biomolecules that are normally considered to be information-bearers (DNA, mRNA) can be shown to be the most specific causes of protein primary structure, provided that causal specificity is measured over a relevant space of biological possibilities, disregarding physical as well as logically possible states of the causal variables. (shrink)

A notion of delegated causality is introduced here. This subtle kind of causality is dual to interventional causality. Delegated causality elucidates the causal role of dynamical systems at the “edge of chaos”, explicates evident cases of downward causation, and relates emergent phenomena to Gödel’s incompleteness theorem. Apparently rich implications are noticed in biology and Chinese philosophy. The perspective of delegated causality supports cognitive interpretations of self-organization and evolution.

Human microbiome research makes causal connections between entire microbial communities and a wide array of traits that range from physiological diseases to psychological states. To evaluate these causal claims, we first examine a well-known single-microbe causal explanation: of Helicobacter pylori causing ulcers. This apparently straightforward causal explanation is not so simple, however. It does not achieve a key explanatory standard in microbiology, of Koch’s postulates, which rely on manipulations of single-microorganism cultures to infer causal relationships to disease. When Koch’s postulates (...) are framed by an interventionist causal framework, it is clearer what the H. pylori explanation achieves and where its explanatory strengths lie. After assessing this ‘simple’, single-microbe case, we apply the interventionist framework to two key areas of microbiome research, in which obesity and mental health states are purportedly explained by microbiomes. Despite the experimental data available, interventionist criteria for explanation show that many of the causal claims generated by microbiome research are weak or misleading. We focus on the stability, specificity and proportionality of proposed microbiome causal explanations, and evaluate how effectively these dimensions of causal explanation are achieved in some promising avenues of research. We suggest some conceptual and explanatory strategies to improve how causal claims about microbiomes are made. (shrink)

Following from my criticisms of Calcott’s analysis on the permissive/instructive distinction, I rebut his claims that 1) he clarifies my measure one-to-one specificity; 2) for all intents and purposes of his analysis his notion of precision is different from my measure of one- to-one specificity; 3) Waddington box is a better and different model than the extension of Woodward’s radio I propose.

The interventionist account provides us with several notions permitting the qualification of causal relationships. In recent years, there has been a push toward formalizing these notions using information theory. In this paper, I discuss one of them, namely causal specificity. The notion of causal specificity is ambiguous as it can refer to at least two different concepts. After having presented these, I show that current attempts to formalize causal specificity in information theoretic terms have mostly focused on one of these (...) two concepts. I then propose and apply a new information-theoretic measure which captures the other concept. (shrink)

The interventionist account of causation offers a criterion to distinguish causes from non-causes. It also aims at defining various desirable properties of causal relationships, such as specificity, proportionality and stability. Here we apply an information-theoretic approach to these properties. We show that the interventionist criterion of causation is formally equivalent to non-zero specificity, and that there are natural, information-theoretic ways to explicate the distinction between potential and actual causal influence. We explicate the idea that the description of causes should be (...) proportional to that of their effects. Then we draw a distinction between two ideas in the existing literature, the range of invariance of a causal relationship and its stability. The range of invariance is related to specificity and range of causal values. Stability concerns the effect of additional variables on the relationship between some focal pair of cause and effect variables. We show how to distinguish and measure the direct influence of background variables on the effect variable, and their influence on the relationship between the focal cause and the effect variable. Finally, we discuss the limitations of the information-theoretic approach, and offer prospects for complementary approaches. (shrink)

I argue that Calcott :481–505, Calcott 2017) mischaracterizes in an important way the notion of causal specificity proposed by Woodward :287–318, Woodward 2010). This leads him to rely too heavily on one single aspect of Woodward’s analysis on causal specificity; propose an information-theoretic measure he calls ‘precision’ which is partly redundant with, but less general than one of the dimensions in Woodward’s analysis of specificity, without acknowledging Woodward’s analysis; and claim that comparing the specificities of two or more causes under (...) what he calls a competitive analysis of causes, does not permit to capture the distinction between permissive and instructive causes. After having restated Woodward’s analysis of causal specificity, I present an information-theoretic measure which, although related to Calcott’s measure, is more general than his and corresponds to the notion of specificity he missed in Woodward's analysis. I then show how this measure can be used, together with mutual causal information, to distinguish permissive from instructive causes in a competitive analysis of causes. (shrink)

I respond to recent criticism of my analysis of the permissive-instructive distinction and outline problems with the alternative analysis on offer. Amongst other problems, I argue that the use of formal measures is unclear and unmotivated, that the distinction is conflated with others that are not equivalent, and that no good reasons are provided for thinking the alternative model or formal measure tracks what biologists are interested in. I also clarify my own analysis where it has been misunderstood or ignored.