Sara Ayhan

"Then Logic would take you by the throat, and force you to do it!"

(Lewis Carroll (1895): "What the Tortoise Said to Achilles")

Homepage of our logic team: Logic in Bochum

About me

(August 2023)

• Since Mai 2023: Post-Doc in the ConLog-ERC Advanced Grant Project of Prof. Dr. Heinrich Wansing: Contradictory Logics - A Radical Challenge to Logical Orthodoxy
• March 2018-April 2023: Research Assistant/PhD Student, Ruhr-University Bochum. Supervisors: Prof. Dr. Heinrich Wansing, Prof. Dr. Greg Restall
• 2018: M. A. Philosophy, Ruhr-University Bochum. Master's Thesis: Proof-theoretic semantics and paradoxes, Supervisor: Prof. Dr. Heinrich Wansing
• 2015: First State Exam in Philosophy, English and History, University of Siegen. State Exam Thesis: Donald Davidson's Conception of Truth, Supervisor: Prof. Dr. Richard Schantz
• 2014: Semester Abroad, University of Adelaide, South Australia
• 2010: Abitur, Städtisches Gymnasium Selm

Publications

• Ayhan, S. (forthcoming): What are acceptable reductions? Perspectives from proof-theoretic semantics and type theory, Australasian Journal of Logic.
• Ayhan, S. & Wansing, H. (2023): On synonymy in proof-theoretic semantics. The case of 2Int, Bulletin of the Section of Logic 52(2), 187-236.
• Ayhan, S. (2023): Introduction: Bilateralism and Proof-Theoretic Semantics (Part I & II), Bulletin of the Section of Logic 52(2&3), 101-108; 265-272.
• Wansing, H. & Ayhan, S. (forthcoming): Logical Multilateralism, Journal of Philosophical Logic.
• Ayhan, S. (2021): What is the Meaning of Proofs? A Fregean Distinction in Proof-Theoretic Semantics, Journal of Philosophical Logic 50, 571–591.
• Ayhan, S. (2021): 
  , in The Logica Yearbook 2020, ed. by Martin Blicha & Igor Sedlár, pp. 1-16, College Publications.
• Ayhan, S. (2020): A cut-free sequent calculus for the bi-intuitionistic logic 2Int, unpublished manuscript: arXiv:2009.14787.

Projects

• PhD-Dissertation (defended in July 2023): Meaning and identity of proofs in (bilateralist) proof-theoretic semantics
• February/March 2023: 4-week research stay hosted by Dave Ripley at Monash University, Melbourne
• Editing Special Issue of the Bulletin of the Section of Logic: Bilateralism and Proof-Theoretic Semantics (Online available here)
• March 17-18, 2022: Organization: Conference: Bilateralism and Proof-Theoretic Semantics, Ruhr University Bochum.
• September 8-10, 2021: Co-Organization: PhDs in Logic XII, Free University Berlin.

New & Upcoming Events

• We (Antonio Piccolomini d'Aragona, Hermógenes Oliveira, Will Stafford and I) are currently making efforts to found the "Proof-Theoretic Semantics Network".
• June 2023: During Logica 2023 I was inducted into the Logicians' Liberation League as "The Refutor".
• July 2023: I successfully defended my PhD thesis.
• September 18-19: I'll be presenting my work at the Symposium on Proof-theoretic Semantics in Prague, co-located with TABLEAUX 2023.
• As of October 2023 I'll be a member of the University Committee for Diversity.
• November 2023: I'm organizing a workshop for the philosophy staff on "Dealing with structural injustice in university teaching".
• December, 6-8, 2023: We're hosting the 1st Workshop on Contradictory Logics.

Talks (Selection)

• Meaning and identity of proofs in a bilateralist setting: A two-sorted typed lambda-calculus for proofs and refutations, June 2023, Logica 2023, Department of Logic, Academy of Sciences of the Czech Republic.
• ‘Bad’ reductions, paradoxes and the meaning of proofs (invited), November 2022, Symposium on Proof-theoretic Semantics, University College London.
• ‘Bad’ reductions, paradoxes and the meaning of proofs, Logica 2022, September 2022, Department of Logic, Academy of Sciences of the Czech Republic.
• Why Ekman-reduction is no reduction (and therefore Ekman’s paradox is no paradox), September 2022, PhDs in Logic XIII, University of Turin.
• Meaning and identity of proofs in a bilateralist setting: A two-sorted typed lambda-calculus for 2Int (invited), August 2022, XI Workshop on Philosophical Logic, Argentinean Society of Philosophical Analysis (SADAF), Buenos Aires.
• How to secure uniqueness of logical connectives in bilateralism (or multilateralism) (invited), Explanatory Inference Seminar, January 2022, Institut supérieur de philosophie, UCLouvain.
• On the distinctions between sense vs. denotation and identity vs. synonymy of proofs (invited, online), Celebrating the World Logic Day - 2022: The meaning of proofs, January 2022, University College London. (Slides)
• Bilateralism, logical consequence, and uniqueness of logical connectives, 25th Oxford Graduate Philosophy Conference, November 2021, University of Oxford.
• Reduction procedures and the meaning of proofs (invited), Seminar on Applied Mathematical Logic, October 2021, Department of Logic, Czech Academy of Sciences, Prague.
• Reduction procedures and the meaning of proofs (online, invited), The Logic Supergroup - Early Career Researcher Workshop, October 2021.
• Bilateralism, logical consequence, and uniqueness of logical connectives, PhD-Konferenz: Open Minds XV, October 2021, University of Manchester.
• Bilateralism, logical consequence, and uniqueness of logical connectives (online, invited), Buenos Aires Logic Group - 10th Workshop on Philosophical Logic, August 2021, University of Buenos Aires.
• Reduction procedures and the meaning of proofs (invited), Łódź-Bochum Workshop, July 2021, Ruhr University Bochum and University of Łódź.
• What are good reduction procedures? Perspectives from proof-theoretic semantics and type theory (online), AAL 2021 - Annual Conference of the Australasian Association for Logic, June 2021, University of Queensland and the University of Melbourne.
• Uniqueness of logical connectives in a bilateralist setting, Logic in Bochum VI, December 2020, Ruhr University Bochum.
• What is the meaning of proofs? A Fregean distinction in proof-theoretic semantics, Thirteenth Annual Cambridge Graduate Conference on the Philosophy of Mathematics and Logic, January 2020, St John's College, Cambridge.
• Uniqueness of logical connectives in a bilateralist setting (invited), Paris-Bochum-Moscow Workshop in Mathematical Philosophy , December 2019, École normale supérieure, Paris.
• The meaning of proofs in different proof systems, PhDs in Logic XI, April 2019, Bern, Institut für Exakte Wissenschaften.
• The meaning of proofs in different proof systems, Proof-Theoretic Semantics: Assessment and Future Perspectives, Third Tübingen Conference on Proof-Theoretic Semantics, March 2019, Eberhard Karls University Tübingen.
• Proof-theoretic semantics and paradoxes: Distinguishing non-standard phenomena in sequent calculus, PhDs in Logic X, Mai 2018, Institute for Philosophy of the Czech Academy of Sciences, Prague.

Teaching

Consultation hours (room GB 04/148) by appointment

Seminars

Past Seminars:

• Exercise class: Logic I (WiSe 2018/19, WiSe 2019/20, WiSe 2021/22, SoSe 2023)
• Paradoxes (WiSe 2018/19, WiSe 2019/20)
• Introduction to Philosophy of Logic (SoSe 2019)
• Block Seminar: Logical Argumentation and Manipulation (SoSe 2019, SoSe 2020, SoSe 2021, WiSe 2022/23)
• Classical Texts in Philosophy of Language - Online-Seminar (SoSe 2020, WiSe 2020/21)
• Introduction to Analytical Philosophy (together with Christopher Badura) - Online-Seminar (SoSe 2020)
• Philosophical Devices (Formal Methods in Philosophy) (Online: WiSe 2020/21, In-Person: SoSe 2022)
• Introduction to General Proof Theory (WiSe 2021/22)

Research Interests

• Philosophical logic: Proof-theoretic semantics, properties of consequence relations, identity of proofs, comparing different proof systems, non-classical logics, (logical) paradoxes
• Philosophy of language/epistemology: Vagueness, theories of truth

Other Interests

For vacation I go on Metal festivals. I'm into all kinds of sports related to fitness or dance, especially ballet, Brazilian Zouk, belly dancing and swimming. To relax, I like baking Baklava for my family and/or colleagues or carving wood, which usually results in tiny spoons.
I was interviewed for a podcast, „Der Funke – Geschichten aus dem Leben“ (Audible Original), about how I came to do my PhD in Logic, what it is like to work in this area (as a woman) and at a university. Here’s a link to the podcast (Episode 17 „In der Fremde zu Gast und in der Logik zu Hause“ - the interview is in German, though).

Videos

• Talk: Reduction procedures and the meaning of proofs (online, invited), The Logic Supergroup - Early Career Researcher Workshop, October 2021.
• Talk: On the distinctions between sense vs. denotation and identity vs. synonymy of proofs (online, invited), Celebrating the World Logic Day - 2022: The meaning of proofs, January 2022, University College London.
• Talk: How to secure uniqueness of logical connectives in bilateralism (or multilateralism) (invited), Explanatory Inference Seminar, January 2022, Institut supérieur de philosophie, UCLouvain.
• Tutorial video (Logica MX Outreach Project): Logic for the understanding of logical connectives