Susanne Bobzien (born 1960) is a German-born philosopherWho'sWho in America 2012, 64th Edition whose research interests focus on philosophy of logic and language, determinism and freedom, and ancient philosophy.Bobzien's British Academy Page
/ref> She currently is senior research fellow at

All Souls College, Oxford All Souls College (official name: College of the Souls of All the Faithful Departed) is a constituent college of the University of Oxford in England. Unique to All Souls, all of its members automatically become fellows (i.e., full members of t ...

and professor of philosophy at the

University of Oxford , mottoeng = The Lord is my light , established = , endowment = £6.1 billion (including colleges) (2019) , budget = £2.145 billion (2019–20) , chancellor ...

.All Souls Faculty Page
/ref>

Early life

Bobzien was born in

Hamburg (male), (female) en, Hamburger(s), Hamburgian(s) , timezone1 = Central (CET) , utc_offset1 = +1 , timezone1_DST = Central (CEST) , utc_offset1_DST = +2 , postal ...

, Germany, in 1960. She graduated in 1985 with an M.A. at Bonn University, and in 1993 with a doctorate in philosophy (D.Phil.) at

Oxford University Oxford () is a city in England. It is the county town and only city of Oxfordshire. In 2020, its population was estimated at 151,584. It is north-west of London, south-east of Birmingham and north-east of Bristol. The city is home to the ...

, where from 1987–1989 she was affiliated with

Somerville College Somerville College, a constituent college of the University of Oxford in England, was founded in 1879 as Somerville Hall, one of its first two women's colleges. Among its alumnae have been Margaret Thatcher, Indira Gandhi, Dorothy Hodgkin, ...

Academic career

Bobzien currently holds the position of senior research fellow at

and is professor of philosophy at

. She was appointed to a senior professorship in philosophy at Yale in 2001Yale Daily News 3/23/2001, "Philosophy hires rising Oxford star"
and held this position from 2002 to 2010. From 1993 to 2002 she had a tenured position at Oxford University. From 1990 to 2002, she was fellow and praelector in philosophy at The Queen's College. Before that she was tutorial fellow in philosophy at

Balliol College Balliol College () is one of the constituent colleges of the University of Oxford in England. One of Oxford's oldest colleges, it was founded around 1263 by John I de Balliol, a landowner from Barnard Castle in County Durham, who provided the f ...

. Among her awards are a British Academy Research Readership (2000–2002),British Academy Research Readerships 2000–2002.
/ref> and a fellowship of the National Endowment for the Humanities (2008–09).
/ref> In 2014 she was elected a

Fellow of the British Academy Fellowship of the British Academy (FBA) is an award granted by the British Academy to leading academics for their distinction in the humanities and social sciences. The categories are: # Fellows – scholars resident in the United Kingdom # C ...

, the United Kingdom's

national academy A national academy is an organizational body, usually operating with state financial support and approval, that co-ordinates scholarly research activities and standards for academic disciplines, most frequently in the sciences but also the humanit ...

for the humanities and social sciences. Bobzien has published several books and numerous articles in leading academic journals and collections.

Philosophical work

Determinism and freedom

Bobzien's major work ''Determinism and Freedom in Stoic Philosophy'' is "the first full-scale modern study of the toictheory f determinism.Times Literary Supplement (15 September 2000) "Chrysippus and the seamless web" "It explores ... the views of the Stoics on causality, fate, the modalities, divination, rational agency, the non-futility of action, moral responsibility, nd theformation of character".Mind 109 (2000) p. 855 In this book and in her articles "The Inadvertent Conception and Late Birth of the Free-Will Problem" and "Did Epicurus discover the Free-Will Problem?" Bobzien argues that the problem of determinism and free-will, as conceived in contemporary philosophy, was not considered by Aristotle, Epicurus or the Stoics, as was previously thought, but only in the 2nd century CE, as the result of a conflation of Stoic and Aristotelian theory.PhilPapers archive link to Bobzien's professional papers
/ref> Bobzien's "Die Kategorien der Freiheit bei Kant" (The Categories of Freedom in Kant) has been described as an article "that has long been the starting point for any German reader seeking to deepen his understanding of the second chapter of the Analytic of Kant's

Critique of Practical Reason The ''Critique of Practical Reason'' (german: Kritik der praktischen Vernunft) is the second of Immanuel Kant's three critiques, published in 1788. It follows on from Kant's first critique, the '' Critique of Pure Reason'' and deals with his mo ...

." It differentiates the main functions of Kant's Categories of Freedom: as conditions of the possibility for actions (i) to be free, (ii) to be comprehensible as free and (iii) to be morally evaluated.Notre Dame Philosophical Reviews, 2010.11.06, of K. Ameriks, O. Höffe (eds.) Kant's Moral and Legal Philosophy, Cambridge 2009.
/ref>

History of logic

Bobzien's ''Die stoische Modallogik''Die stoische Modallogik (Würzburg 1986) is the first monograph on Stoic modal logic.K. Hülser, ''Die Fragmente zur Dialektik der Stoiker'', vol. 3. p. VI. In her paper "Stoic Syllogistic" Bobzien sets out the evidence for Stoic syllogistic. She argues that this should not be assimilated into standard propositional calculus, but treated as a distinct system which bears important similarities to

relevance logic Relevance logic, also called relevant logic, is a kind of non-classical logic requiring the antecedent and consequent of implications to be relevantly related. They may be viewed as a family of substructural or modal logics. It is generally, but ...

and

connexive logic Connexive logic names one class of alternative, or non-classical, logics designed to exclude the paradoxes of material implication. The characteristic that separates connexive logic from other non-classical logics is its acceptance of Aristotle's t ...

.Review of Oxford Studies in Ancient Philosophy XIV, 1996. In "Stoic Sequent Logic and Proof Theory", she argues that stoic deduction resembles backward proof search for

Gentzen Gerhard Karl Erich Gentzen (24 November 1909 – 4 August 1945) was a German mathematician and logician. He made major contributions to the foundations of mathematics, proof theory, especially on natural deduction and sequent calculus. He died o ...

-style substructural

sequent In mathematical logic, a sequent is a very general kind of conditional assertion. : A_1,\,\dots,A_m \,\vdash\, B_1,\,\dots,B_n. A sequent may have any number ''m'' of condition formulas ''Ai'' (called " antecedents") and any number ''n'' of asse ...

logics as developed in structural proof theory,''History and Philosophy of Logic'' 2019.
/ref> and in the co-authored "Stoic Logic and Multiple Generality" she lays out evidence that Stoic logic could handle the

problem of multiple generality The problem of multiple generality names a failure in traditional logic to describe certain intuitively valid inferences. For example, it is intuitively clear that if: :''Some cat is feared by every mouse'' then it follows logically that: :''All m ...

in a variable-free

first-order logic First-order logic—also known as predicate logic, quantificational logic, and first-order predicate calculus—is a collection of formal systems used in mathematics, philosophy, linguistics, and computer science. First-order logic uses quantifie ...

.''Philosophers' Imprint'' 2020.
/ref> Bobzien's paper "The Development of Modus Ponens in Antiquity" traces the earliest development of

modus ponens In propositional logic, ''modus ponens'' (; MP), also known as ''modus ponendo ponens'' (Latin for "method of putting by placing") or implication elimination or affirming the antecedent, is a deductive argument form and rule of inference. ...

(or Law of Detachment).PhilPapers
/ref>The Development of Modus Ponens in Antiquity", ''Phronesis'' 47, 2002
/ref> She has also reconstructed the ancient history of

hypothetical syllogism In classical logic, a hypothetical syllogism is a valid argument form, a syllogism with a conditional statement for one or both of its premises. An example in English: :If I do not wake up, then I cannot go to work. :If I cannot go to work, then ...

s''Phronesis'' 45, 2002, 87–137.
/ref> and Galen's representation of peripatetic hypothetical syllogistic, and shown these differ from stoic syllogistic and contemporary propositional logic.''Rhizai Journal for Ancient Philosophy and Science'' 2, 2004, 57–102. In the 2021 extended essay "Frege plagiarized the Stoics", based on her 2016 Keeling Lecture, Bobzien argues in detail that Frege plagiarized them on a large scale in his work on the philosophy of logic and language, written mainly between 1890 and his death in 1925.''Themes in Plato, Aristotle, and Hellenistic Philosophy: Keeling Lectures 2011-18''
London: 2020.

Vagueness and paradoxes

Bobzien has worked on the philosophical application of the

modal logic Modal logic is a collection of formal systems developed to represent statements about necessity and possibility. It plays a major role in philosophy of language, epistemology, metaphysics, and natural language semantics. Modal logics extend other ...

S4.1 to vagueness and paradoxes. She has introduced and developed the philosophical ideas of columnar higher-order vagueness, borderline nestings, and semi-determinability.Mormann, ''Erkenntnis'' 2020.
/ref>''Analytic Philosophy'' 2013.
/ref>''Notre Dame Philosophical Review''.
/ref> In "Gestalt Shifts in the Liar", presented in he
2017 Jacobsen Lecture
Bobzien analyses three features of liar sentences and shows how their combination leads to the liar's paradoxicality: salience-based

bistability In a dynamical system, bistability means the system has two stable equilibrium states. Something that is bistable can be resting in either of two states. An example of a mechanical device which is bistable is a light switch. The switch lever ...

, context sensitivity, and assessment sensitivity. On this basis she proposes the modal logic S4.1 as governing the truth operator and offers a revenge-free solution to the liar paradox that relates to Herzberger's revision theory of truth. Bobzien has proposed a logic of higher-order

vagueness In linguistics and philosophy, a vague predicate is one which gives rise to borderline cases. For example, the English adjective "tall" is vague since it is not clearly true or false for someone of middling height. By contrast, the word "prime" is ...

(the quantified modal logic S4.1 supplemented with

Max Cresswell Maxwell John Cresswell (born 19 November 1939) is a New Zealand philosopher and logician, known for his work in modal logic.''Festschrift for Max Cresswell on the occasion of his 65th birthday.'' In: ''Logique et Analyse.'' Number 181, March 2 ...

's Finality Axiom) that delivers a generic solution to the

Sorites paradox The sorites paradox (; sometimes known as the paradox of the heap) is a paradox that results from vague predicates. A typical formulation involves a heap of sand, from which grains are removed individually. With the assumption that removing a sing ...

and avoids higher-order vagueness paradoxes and sharp boundaries.''Philosophers' Imprint'' 2010
/ref>''Aristotelian Society Suppl.'' 89, 2015.
/ref> The proposed logic is weaker than

classical logic Classical logic (or standard logic or Frege-Russell logic) is the intensively studied and most widely used class of deductive logic. Classical logic has had much influence on analytic philosophy. Characteristics Each logical system in this class ...

and stronger than

intuitionistic logic Intuitionistic logic, sometimes more generally called constructive logic, refers to systems of symbolic logic that differ from the systems used for classical logic by more closely mirroring the notion of constructive proof. In particular, systems ...

. It is a

modal companion In logic, a modal companion of a superintuitionistic (intermediate) logic ''L'' is a normal modal logic that interprets ''L'' by a certain canonical translation, described below. Modal companions share various properties of the original intermediat ...

to the superintuitionistic logic QH+KF.Bobzien Faculty Page
/ref>

Selected publications

Determinism and freedom
and Freedom in Stoic Philosophy''
(Oxford 1998).
Freedom, and Moral Responsibility: Essays in Ancient Philosophy''
(Oxford 2021). *"The Inadvertent Conception and Late Birth of the Free-Will Problem" (''Phronesis'' 43, 1998) *"Did Epicurus Discover the Free-Will Problem?" (''Oxford Studies in Ancient Philosophy'' 19, 2000) *"Die Kategorien der Freiheit bei Kant" (in ''Kant: Analysen-Probleme-Kritik'' vol. 1, Würzburg, 1988) History of logic *''Die stoische Modallogik'' (Würzburg 1986). *''Alexander of Aphrodisias: On Aristotle Prior Analytics 1.1-7'', with J. Barnes, K. Flannery, K. Ierodiakonou (London 1991). *"Stoic Syllogistic" (''Oxford Studies in Ancient Philosophy'' 14, 1996). *"The Development of Modus Ponens in Antiquity" (''Phronesis'' 47, 2002)
"Stoic Sequent Logic and Proof Theory"
(''History and Philosophy of Logic'' 40, 2019)
“Stoic Logic and Multiple Generality”
with Simon Shogry (''Philosophers’ Imprint'' 20, 2020)
"Frege Plagiarized the Stoics"
(in ''Themes in Plato, Aristotle, and Hellenistic Philosophy: Keeling Lectures 2011-18'', London 2021) Vagueness and paradoxes
"Higher-order Vagueness, Radical Unclarity, and Absolute Agnosticism"
(''Philosophers' Imprint'' 10, 2010)
"In Defense of True Higher-Order Vagueness"
(''Synthese'' 180, 2011)
"If it's Clear, then it's Clear that it's Clear, or is it? – Higher-Order Vagueness and the S4 Axiom"
(Oxford 2012)
"Higher-Order Vagueness and Borderline Nestings – a Persistent Confusion"
(''Analytic Philosophy'' 54.1, 2013).
"Columnar Higher-order Vagueness or Vagueness is Higher-Order Vagueness"
(''Aristotelian Society Suppl.'' 89, 2015)
"Gestalt Shifts in the Liar or Why KT4M is the Logic of Semantic Modalities"
(in ''Reflections on the Liar'', Oxford 2017)
"Intuitionism and the Modal Logic of Vagueness"
with Ian Rumfitt (''Journal of Philosophical Logic'' 49, 2020)

References

External links

*
Homepage at All Souls College, OxfordWomen in Logic
{{DEFAULTSORT:Bobzien, Susanne 20th-century British philosophers 20th-century German philosophers 21st-century British philosophers 21st-century German philosophers Yale University faculty German scholars of ancient Greek philosophy Philosophers of language German women philosophers Living people 1960 births Fellows of the British Academy Fellows of All Souls College, Oxford Alumni of Somerville College, Oxford 20th-century German women