Logical Relevance in English Evidence Law:

Its History and Impact on Keynes and Russell

Jan Dejnožka

summary, praise,

and ordering information


Logical relevance is an essential feature of evidence for both John Maynard Keynes and Bertrand Russell - and also for the last five centuries of English evidence law. If it is not relevant, it is not evidence. If it is not evidence, it is not relevant. It has been widely held that Keynes himself invented the theory that probability is degree of logical relevance. This book is the first study of the legal origins of Keynes' and Russell's logicist theories of probability. Like Dejnožka's other books, this book upends received thought. Following J. L. Montrose, whom he anthologizes, the legal scholar William Twining denies that some of the great evidence law writers had relevance rules. Dejnožka quotes and discusses the relevance rules of those writers. The Keynes scholar Robert Skidelsky holds that Keynes himself discovered the relation between probability and logical relevance. Dejnožka quotes and discusses that relation as affirmed throughout the last five centuries of English evidence law. Most relevantists were members of the Inner Temple law bar, and Keynes was too

Praise for the book

"Jan Dejnožka’s Logical Relevance in English Evidence Law innovatively explores the links between the evolution of the Anglo-American law of evidence and the philosophical investigations of Keynes and Russell. He provides a fascinating interdisciplinary examination between two disciplines not ordinarily studied together. Dejnožka’s study should be of interest to scholars interested in evidence, regardless of discipline." —Barbara J. Shapiro

Barbara J. Shapiro is professor emerita of rhetoric at the University of California at Berkeley. Her books include Beyond Reasonable Doubt and Probable Cause: Historical Perspectives on the Anglo-American Law of Evidence (University of California Press) and Probability and Certainty in Seventeenth-Century England: A Study of the Relationships Between Science, Religion, History, Law, and Literature (Princeton University Press).

"Dejnožka challenges the reader to open his mind for a new interpretation of Russell’s work, in particular that relevance notions have a greater place in his philosophy of logic than has been stressed before. Dejnožka’s work is full of material which stimulates one to rethink Russell’s philosophy of logic, and it is greatly to the author’s credit that he brings to light such a wealth of crucial issues in the history and philosophy of logic." —Shahid Rahman

Shahid Rahman is exceptional professor of logic and epistemology at the Université de Lille 3 (Charles de Gaulle). He was Director (for the French side) of the du ANR-DFG Franco-German project 2012–2015 (Lille (MESHS)/Konstanz, Prof M. Armgardt): Théorie du Droit et Logique / Jurisprudenz und Logik. His recent papers include “Conditionals and Legal Reasoning: Elements of a Logic of Law,” HAL 2017 (with Bernadette Dango), and “Unfolding Parallel Reasoning in Islamic Jurisprudence: Epistemic and Dialectical Meaning in Abū Ishāq al-Shīrāzī’s System of Co-Relational Inferences of the Occasioning Factor,” Cambridge Journal of Arabic Sciences and Philosophy 2018 (with Muhammad Iqbal).

"I have spent my career researching the role of relevance in logic, and I found this book highly ‘relevant’. It points out the profound role that English evidence law had in influencing two of the founders of probability theory and logic, Keynes and Russell. It is well written and very interesting." —J. Michael Dunn

J. Michael Dunn is professor emeritus of computer science and informatics, Oscar Ewing professor emeritus of philosophy, and founding dean emeritus of the School of Informatics at Indiana University. He was a co-editor of Entailment: The Logic of Relevance and Necessity, volume 2 (Princeton University Press).

Ordering Information

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