Holly Andersen

In this field guide, I distinguish five separate senses with which the term ‘mechanism’ is used in contemporary philosophy of science. Many of these senses have overlapping areas of application but involve distinct philosophical claims and characterize the target mechanisms in relevantly different ways. This field guide will clarify the key features of each sense and introduce some main debates, distinguishing those that transpire within a given sense from those that are best understood as concerning two distinct senses. The ‘new mechanisms’ sense is the primary sense from which other senses will be distinguished. In part II of this field guide, I consider three further senses of the term that are ontologically ‘flat’ or at least not explicitly hierarchical in character: equations in structural equation models of causation, causal-physical processes, and information-theoretic constraints on states available to systems. After characterizing each sense, I clarify its ontological commitments, its methodological implications, how it figures in explanations, its implications for reduction, and the key manners in which it differs from other senses of mechanism. I conclude that there is no substantive core meaning shared by all senses, and that debates in contemporary philosophy of science can benefit from clarification regarding precisely which sense of mechanism is at stake

In the recent literature on causal and non-causal scientific explanations, there is an intuitive assumption according to which an explanation is non-causal by virtue of being abstract. In this context, to be ‘abstract’ means that the explanans in question leaves out many or almost all causal microphysical details of the target system. After motivating this assumption, we argue that the abstractness assumption, in placing the abstract and the causal character of an explanation in tension, is misguided in ways that are independent of which view of causation or causal explanation one takes to be most accurate. On major accounts of causation, as well as on major accounts of causal explanation, the abstractness of an explanation is not sufficient for it being non-causal. That is, explanations are not non-causal by dint of being abstract.

William James’ Principles of Psychology, in which he made famous the ‘specious present’ doctrine of temporal experience, and Edmund Husserl’s Zur Phänomenologie des inneren Zeitbewusstseins, were giant strides in the philosophical investigation of the temporality of experience. However, an important set of precursors to these works has not been adequately investigated. In this article, we undertake this investigation. Beginning with Reid’s essay ‘Memory’ in Essays on the Intellectual Powers of Man, we trace out a line of development of ideas about the temporality of experience that runs through Dugald Stewart, Thomas Brown, William Hamilton, and finally the work of Shadworth Hodgson and Robert Kelly, both of whom were immediate influences on James (though James pseudonymously cites the latter as ‘E.R. Clay’). Furthermore, we argue that Hodgson, especially his Metaphysic of Experience (1898), was a significant influence on Husserl.

Even though the evidence‐based medicine movement (EBM) labels mechanisms a low quality form of evidence, consideration of the mechanisms on which medicine relies, and the distinct roles that mechanisms might play in clinical practice, offers a number of insights into EBM itself. In this paper, I examine the connections between EBM and mechanisms from several angles. I diagnose what went wrong in two examples where mechanistic reasoning failed to generate accurate predictions for how a dysfunctional mechanism would respond to intervention. I then use these examples to explain why we should expect this kind of mechanistic reasoning to fail in systematic ways, by situating these failures in terms of evolved complexity of the causal system(s) in question. I argue that there is still a different role in which mechanisms continue to figure as evidence in EBM: namely, in guiding the application of population‐level recommendations to individual patients. Thus, even though the evidence‐based movement rejects one role in which mechanistic reasoning serves as evidence, there are other evidentiary roles for mechanistic reasoning. This renders plausible the claims of some critics of evidencebased medicine who point to the ineliminable role of clinical experience. Clearly specifying the ways in which mechanisms and mechanistic reasoning can be involved in clinical practice frames the discussion about EBM and clinical experience in more fruitful terms.

This chapter examines the philosophical discussion concerning the relationship between time, memory, attention, and consciousness, from Locke through the Scottish Common Sense tradition, in terms of its influence on James' development of the specious present doctrine. The specious present doctrine is the view that the present moment in experience is non punctate, but instead comprises some nonzero amount of time; it contrasts with the mathematical view of the present, in which the divide between past and future is merely a point or a line with no thickness. The anonymous source for the term 'specious present' is revealed as a retired businessman-turned-amateur philosopher. The more likely source for the idea itself is a little-known philosopher, Shadworth Hollway Hodgson, who was not merely a significant influence on James but also on Husserl's development of the tripartite account of internal time consciousness. I conclude by demonstrating how James' changing views on the relationship between concepts and experience meant that by the later period of his writings, including those in which he develops his own views on pragmatism, James would have not merely noted the contrast between a mathematical conception of the present and our actual experience of it, he would have taken a further step and condoned the thick experience of the present as demonstrating the inadequacy of the intellectualized mathematical characterization.

This chapter offers a overview of Shadworth Hodgson's account of experience as fundamentally temporal, an account that was deeply influential on thinkers such as William James and which prefigures the phenomenology of Husserl in many ways. I highlight eight key features that are characteristic of Hodgson's account, and how they hang together to provide a coherent overall picture of experience and knowledge. Hodgson's account is then compared to Husserl's, and I argue that Hodgson's account offers a better target for projects such as neurophenomenology than does Husserl's. Hodgson's account is historically important as a culmination of a certain trajectory of British Empiricist thought. It offers a substantive alternative for how to think about temporality and experience in contemporary discussions, not just of the present moment but of the relationship between experience and knowledge more broadly.

A finer-grained delineation of a given explanandum reveals a nexus of closely related causal and non- causal explanations, complementing one another in ways that yield further explanatory traction on the phenomenon in question. By taking a narrower construal of what counts as a causal explanation, a new class of distinctively mathematical explanations pops into focus; Lange’s characterization of distinctively mathematical explanations can be extended to cover these. This new class of distinctively mathematical explanations is illustrated with the Lotka-Volterra equations. There are at least two distinct ways those equations might hold of a system, one of which yields straightforwardly causal explanations, but the other of which yields explanations that are distinctively mathematical in terms of nomological strength. In the first, one first picks out a system or class of systems, finds that the equations hold in a causal -explanatory way; in the second, one starts with the equations and explanations that must apply to any system of which the equations hold, and only then turns to the world to see of what, if any, systems it does in fact hold. Using this new way in which a model might hold of a system, I highlight four specific avenues by which causal and non- causal explanations can complement one another