Chains of Life: Turing, Lebensform, and the Emergence of Wittgenstein’s Later Style


  • Juliet Floyd Boston University



Lebensform, form of life, Wittgenstein Ludwig, logic, Turing Alan, Philosophical Investigations, Früfassung, Urfassung


This essay accounts for the notion of Lebensform by assigning it a logical role in Wittgenstein’s later philosophy. Wittgenstein’s additions of the notion to his manuscripts of the PI occurred during the initial drafting of the book 1936-7, after he abandoned his effort to revise The Brown Book. It is argued that this constituted a substantive step forward in his attitude toward the notion of simplicity as it figures within the notion of logical analysis. Next, a reconstruction of his later remarks on Lebensformen is offered which factors in his reading of Alan Turing’s “On computable numbers, with an application to the Entscheidungsproblem“ (1936/7), as well as his discussions with Turing 1937-1939. An interpretation of the five occurrences of Lebensform in the PI is then given in terms of a logical “regression” to Lebensform as a fundamental notion. This regression characterizes Wittgenstein’s mature answer to the question, “What is the nature of the logical?”

Author Biography

Juliet Floyd, Boston University

Juliet Floyd is Professor of Philosophy at Boston University. Her research focuses on the interplay between logic, mathematics, and philosophy in the 18th, 19th and 20th centuries, as well as current philosophical implications of emerging computational technologies. Her writings on the history of twentieth century analytic philosophy span a diverse array of topics, including foundations of mathematics, aesthetics, modernism, political philosophy, ordinary language philosophy, and American philosophy. She has co-edited (with S. Shieh) Future Pasts: The Analytic Tradition in Twentieth Century Philosophy (Oxford University Press, 2001), (with J. E. Katz) Philosophy of Emerging Media: Understanding, Appreciation, Application (Oxford, 2016) and (with A. Bokulich) Philosophical Aspects of the Legacy of Alan Turing: Turing 100 (Springer, forthcoming). Her current manuscript explores the significance of the philosophical interactions between Wittgenstein, Turing and Gödel in the 1930s and 40s.


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