Believing the Evidence

The study of ancient religion, partly in response to anthropology, moved in recent decades away from thinking in terms of ‘belief’ to studying ‘ritual’: this has a fundamental effect on how we treat the evidence (or decide what evidence is, and what it is evidence of). This chapter argues that the transition is incomplete and explores some of the deeper implications of thinking in terms of ‘belief’. It argues that these continue to hamper our perspective on ancient religion. The ‘otherness’ of ancient religion does not reside in the ‘rationality’ of their thinking, rather, it is axiomatic (their crediting ritual with power to effect changes in the wider world).

Are there Universal Principles or Forms of Evidential Inference? Of Inference Networks and Onto-Epistemology

This chapter discusses the limitations of approaches to modelling and handling evidential issues using hierarchical network representations. Such models of evidential inference rest on the compound proposition that real-world evidential inference usually or always consists of propositional ‘atoms’ (i.e. relatively granular propositional statements about states of the world) that are linked together by nomological entities of some kind, entities that are often — but not always — called ‘generalisations’. These sorts of models or representations of evidential inference are referred to as ‘network-and-generalisation’ models of evidential inference. It is argued that for certain important problems, especially where these concern meaning and human understanding, these need to be complemented by other methods.

Generalisations and Evidential Reasoning

This chapter suggests that evidence should be viewed as a field of study, one to which most disciplines could contribute and from which most could benefit, and that generalisations should be viewed as part of that field. Every argument must be based upon a generalisation that can be stated as a major premise. The relationship between a supporting proposition or propositions and an inferred proposition can be restated in a quasi-deductive form by identifying the generalisation upon which the inference depends. A datum or a proposition can be evidence if and only if it alters the probability, positively or negatively, of a proposition to be inferred. In order to demonstrate that an evidential proposition is relevant, an analyst must be able to identify and articulate a generalisation that justifies the claim that the evidential proposition alters the probability of an inferred proposition. This chapter develops these ideas and presents a method of generalisation-analysis. It also argues that generalisation-analysis is a tool in the field of evidence that could be useful in analysing and critiquing arguments in many disciplines.

Arguing about the Evidence: a Logical Approach

This chapter explores ways in which we can be equally rigorous about how to reason about and assess uncertain evidence, using a framework that allows for uncertainty but does not depend on being able to quantify it. It begins by defining what is meant by ‘evidence’ since it has somewhat different interpretations in different fields. It then attempts to develop a unified perspective. The central idea of this unification is that it is based on logic and the patterns of argumentation which are to be seen in deliberations and debates about evidence. The framework does not reject the importance of probabilistic methods for reasoning about evidence but offers a broader perspective which accommodates probabilistic methods when they are practical, and offers an alternative set of methods when they are not.

Introduction*

This introductory chapter begins with a brief discussion of the lack of attention to the nature of evidence. It then describes the interdisciplinary research programme ‘Evidence, Inference and Enquiry: Towards an Integrated Science of Evidence’ (generally known simply as the ‘Evidence Programme’), established at University College London in 2004. An overview of the subsequent chapters is also presented.

Rhetoric, Evidence and Policymaking: a Case Study of Priority Setting in Primary Care*

This chapter describes a study undertaken as part of the UCL Evidence programme to explore how policymakers talk about and reason with evidence. Specifically, researchers were interested in the micro-processes of deliberation and meaning-making practices of a group of people charged with prioritising health care in an NHS Primary Care Trust in the UK. The chapter describes how the research study brought together ideas from rhetorical theory and methods of discourse analysis to develop an innovative approach to exploring how evidence is constituted at the micro-level of social interaction and communication. It presents empirical data to illuminate the representation and meaning of evidence within one particular policymaking forum, and to highlight contrasting constructions of the policymaking process.

A Theory of Evidence for Evidence-Based Policy

Evidence-based policy is all the rage now. But no one knows quite how to do it. Policy questions do not generally fall neatly within any one of our scientific or social science disciplines, where the standards and rules of evidence for the questions studied are fairly clearly delineated. There is by now a variety of guides available on standards of evidence for evidence-based policy. But these focus narrowly on only part of the problem. This chapter lays the foundations for a guide for the use of evidence in predicting policy effectiveness in situ — a more comprehensive guide than current standard offerings such as the Maryland rules in criminology, the weight of evidence scheme of the International Agency for Research on Cancer, or the US ‘What Works Clearinghouse’. The guide itself is meant to be well-grounded but at the same time to give practicable advice, that is, advice that can be used by policy-makers not experts in the natural and social sciences, assuming they are well-intentioned and have a reasonable but limited amount of time and resources available for searching out evidence and deliberating.

In Praise of Randomisation: The Importance of Causality in Medicine and its Subversion by Philosophers of Science

The job of scientists is to try to distinguish what is true from what is false by means of observation and experiment. That job has been made difficult by some philosophers of science who appear to give academic respectability to relativist, and even postmodernist, postures. This chapter suggests that the contributions of philosophers to causal understanding have been unhelpful. It puts the case for randomised studies as the safest guarantee of the reliability of scientific evidence. It uses the case of hormone replacement therapy to illustrate the importance of randomisation, and the case of processed meat and cancer to illustrate the problems that arise in the absence of randomised tests. Finally, it discusses the opposition to randomisation that has come from some philosophers of science.

What the Ravens Really Teach Us: the Intrinsic Contextuality of Evidence

This chapter advances a contextual view of evidence, through a reconsideration of Hempel's paradox of confirmation (the ‘ravens paradox’). The initial view regarding Hempel's paradox is that a non-black non-raven does confirm ‘All ravens are black’, but only in certain contexts. The chapter begins by reformulating the paradox as a puzzle about how the same entity can have variable evidential values for a given proposition. It then offers a three-stage solution to the reformulated paradox. (1) The situation makes better sense when we reach a deeper propositional understanding of evidence, recognising that each entity can be represented in multiple observational propositions. (2) Some anti-contextualist intuitions can be defused by distinguishing two different senses of the word ‘evidence’, one applying to objects or events and the other applying to propositions; only the latter is relevant to inference. (3) A fuller understanding comes from analysing the constitution and use of evidence in terms of epistemic action. These reflections on the ravens paradox suggest a general philosophical framework more suitable for understanding the function of evidence in scientific and everyday practices.

Moving Beyond Law: Interdisciplinarity and the Study of Evidence

This chapter examines critically both the idea of ‘a multidisciplinary field’ or ‘an integrated science’ of evidence, and scepticism about and resistance to this idea from the standpoint of a jurist who has been involved with interdisciplinary work on evidence in law for many years. The chapter is organized as follows. Part I presents an overview of the intellectual history of the academic study of evidence in law in the Anglo‐American tradition and shows how important aspects of the field came to be recognised as inherently multidisciplinary. Part II identifies some limitations of legal perspectives on evidence, especially when the focus is on contested trials. It recounts the story of attempts to move beyond law in the direction of constructing a general field of evidence that formed part of the background of the UCL programme. Part III examines some of the reasons for suspicion of and resistance to the idea of ‘an integrated science of evidence’. Part IV restates the case for recognition and institutionalisation of evidence as a special focus of attention at the present time and puts forward a personal agenda of general questions that still need to be tackled.