The 28th International Conference on Automated Deduction


The conference on Automated Deduction (CADE) is the major international forum at which research on all aspects of automated deduction is presented. The conference programme includes invited talks, paper presentations, workshops, tutorials, and system competitions. Furthermore, the Herbrand Award for Distinguished Contributions to Automated Deduction, the new Skolem Award(s) for influential historical CADE papers, and the Bill McCune PhD Award, are presented at the conference.

The 28th International Conference on Automated Deduction (CADE-28) will be virtual due to the COVID-19 pandemic. The virtual conference will take place from July 11 to 16, 2021 as originally planned.

Submissions to CADE-28 can be made in two categories: Regular papers (up to 15 pages in LNCS style, excluding references) and short papers (up to 10 pages in LNCS style, excluding references). More information about submission can be found in the joint Call for Papers and Workshops/Tutorials/Competitions.

The authors of a selection of the best CADE-28 papers will be invited to submit an extended version of their paper after the conference, to be published in a special issue of the Journal of Automated Reasoning.

CADE-28 is organized in cooperation with ACM SIGLOG.

Gates Hillman Center at CMU


All dates are Anywhere on Earth.


Workshops+Tutorials: July 11 and 16, 2021
Conference: July 12 - 15, 2021


Papers must be submitted to the CADE-28 track via EasyChair.
All papers must include the ORCID ids of authors (at least the corresponding author).

Abstract deadline: February 15, 2021
Submission deadline: February 22, 2021 (AoE, no extensions)
Rebuttal phase: March 29 to March 31, 2021
Notification: April 9, 2021
Final version: April 30, 2021

Invited Speakers

Liron Cohen, Ben-Gurion University

Title: Non-well-founded deduction for induction and coinduction

Bio: Liron Cohen is senior lecturer (assistant professor) in the Department of Computer Science at Ben-Gurion University in Israel. Previously, Liron was a Fulbright postdoctoral researcher at Cornell University working with Robert Constable. She obtained her Ph.D. in 2016 from Tel Aviv University advised by Arnon Avron. Liron's research is motivated by the desire to understand the deep connection between proofs and computation. Her research interests include computer-aided deduction and verification, type systems, logics, programming languages and computational mathematics.

Guido Governatori, CSIRO

Title: Computational Law: Automated Reasoning in the Legal Domain

Bio: Guido Governatori leads the Software Systems Research Group and research activities on legal informatics at CSIRO's Data61. He received his PhD in Legal Informatics from the University of Bologna. His research has focused on automated reasoning techniques for non-classical logic, modal logic and non-monotonic reasoning (including labelled tableaux for modal logic, rule-based systems, and defeasible logic), and their applications in the legal domain, autonomous agents and business processes.

Mooly Sagiv, Tel Aviv University

Title: Taming Verification Conditions for Diagnosable Verification

Bio: Mooly Sagiv is a professor in the School of Computer Sciences at Tel-Aviv University and a CEO and co-founder of Certora. He is a leading researcher in the area of large scale (inter-procedural) program analysis, and one of the key contributors to shape analysis. His fields of interests include programming languages, compilers, abstract interpretation, profiling, pointer analysis, shape analysis, inter-procedural dataflow analysis, program slicing, and language-based programming environments.

Markus Rabe, Google

Title: What are the Limits of Neural Networks for Automated Reasoning?

Bio: Markus N. Rabe is a software engineer and researcher at Google. He explores the foundations of automated reasoning, including the use of deep learning, and is a member of the N2Formal team, which has the goal to automatically formalize mathematics. Markus has a Ph.D. from Saarland University and visited UC Berkeley as a postdoc.

Co-Located Events


July 11
Theorem Proving Components for Educational Software (ThEdu'21)

Workshop on Proof eXchange for Theorem Proving (PxTP)

Parallel and Distributed Automated Reasoning

July 16
17th International Workshop on Termination (WST 2021)

International Workshop on Logical Frameworks and Meta-Languages: Theory and Practice (LFMTP)

3rd International Workshop on Automated Reasoning: Challenges, Applications, Directions, Exemplary Achievements (ARCADE)


July 11
Program Validation and Verification in PVS
Paolo Masci (NIA), Mariano Moscato (NIA), César Munoz (NASA), Aaron Dutle (NASA), and Tanner Slagel (NASA)

This tutorial provides a gentle introduction to PVS 7.1, recently released, through the most recent versions of NASALib and VSCode-PVS. The tutorial is structured as a hands-on activity with lectures and exercises. Attendees are encouraged to bring their own laptops (Linux or Mac OSX).

Practice of First-Order Reasoning
Stephan Schulz (DHBW), Adam Pease (Articulate Software), and Geoff Sutcliffe (University of Miami)

The tutorial will use PyRes, a simple but complete automatic theorem prover for first-order logic. PyRes has been particularly designed with a pedagogical purpose in mind. It is written in clear, extensively documented Python code. The tutorial will acquaint the participants with the architecture and implementation of a saturating first-order reasoning system. The morning sessions will comprise presentations on the most important aspects of resolution-based theorem proving and their realization in PyRes. Afternoon sessions will be supervised programming exercises by the participants, with the goal of building improved variants of the prover.
The tutorial will conclude with a small CASC-like competition where the different teams can compare the effects of their improvements. Systems that perform well will be eligible for late entry into the demonstration division of CASC.

July 16
Learning to Prove: Machine Learning for Better SAT and QSAT Solvers
Sean Holden (Univeristy of Cambridge)

Satisfiability (SAT) and quantified satisfiability (QSAT) solvers are a fundamental concern for the field of Automated Deduction. While machine learning (ML) is currently an immensely fashionable area, it might not be apparent to many that ML researchers have been applying their work to SAT and QSAT solvers since the late 1980s; and, in fact, numerous aspects of various state-of-the-art solvers employ ele- ments of ML. More recently SAT and QSAT solvers have become an application of interest within the area of deep ML, and the application of these techniques turns out to raise new issues. This tutorial aims to provide an overall introduction to how ML has been applied to date to SAT and QSAT solving, with the aim of providing interested researchers with sufficient background to help move the field forward.

Proof-Theoretical Analysis of Non-Fregean Logic
Szymon Chlebowski, Marta Gawek, Dorota Leszczyńska-Jasion, and Agata Tomczyk (Adam Mickiewicz University)

The tutorial focuses on proof-theory for non-Fregean logics. We will pay special attention to structural proof theory taking into considerations sequent systems and natural deduction systems. The issues of cut-elimination and normalization will be discussed. However, we will also present tableau systems (Rasiowa-Sikorski formalization, dual tableaux, synthetic tableaux) for non-Fregean logics. Finally, we will sketch the ideas how to use the variety of proof systems in facilitating automated proof search in propositional logics with identity.


The CADE ATP System Competition (CASC)

Termination and Complexity Competition (termCOMP)


PC Chairs

André Platzer, Carnegie Mellon University
Geoff Sutcliffe, University of Miami

Local Organizers

Marijn Heule, Carnegie Mellon University
André Platzer, Carnegie Mellon University
Iliano Cervesato, Carnegie Mellon University

Workshop and Tutorial Chair

Alexander Steen, University of Luxembourg

Publicity Chair

Sophie Tourret, Max Planck Institute

Program Committee

Peter Baumgartner, CSIRO
Bernhard Beckert, Karlsruhe Institute of Technology
Christoph Benzmüller, Freie Universität Berlin
Armin Biere, Johannes Kepler University Linz
Nikolaj Bjorner, Microsoft
Jasmin Blanchette, Vrije Universiteit Amsterdam
Maria Paola Bonacina, Università degli Studi di Verona
Agata Ciabattoni, Vienna University of Technology
Koen Claessen, Chalmers University of Technology
Hans de Nivelle, School of Engineering and Digital Sciences Nazarbayev University
Stéphane Demri, LSV CNRS ENS Paris-Saclay
Huimin Dong, Zhejiang University
Gilles Dowek, INRIA and ENS Paris-Saclay
Mnacho Echenim, University of Grenoble
Pascal Fontaine, Université de Liège Belgium
Nathan Fulton, IBM
Silvio Ghilardi, Dipartimento di Matematica Università degli Studi di Milano
Jürgen Giesl, RWTH Aachen University
Rajeev Gore, The Australian National University
Nao Hirokawa, JAIST
Moa Johansson, Chalmers University of Technology
Dejan Jovanović, SRI International
Cezary Kaliszyk, University of Innsbruck
Laura Kovacs, Vienna University of Technology
Tomer Libal, American University of Paris
Assia Mahboubi, INRIA
Cláudia Nalon, University of Brasília
Vivek Nigam, fortiss GmbH
Tobias Nipkow, Technical University of Munich
Frank Pfenning, Carnegie Mellon University
Giles Reger, The University of Manchester
Andrew Reynolds, University of Iowa
Philipp Ruemmer, Uppsala University
Katsuhiko Sano, Faculty of Humanities and Human Sciences Hokkaido University
Renate A. Schmidt, The University of Manchester
Stephan Schulz, DHBW Stuttgart
Viorica Sofronie-Stokkermans, University Koblenz-Landau
Martin Suda, Czech Technical University in Prague
Tanel Tammet, Tallinn University of Technology
Sophie Tourret, Max Planck Institute for Informatics
Josef Urban, Czech Technical University in Prague
Christian Urban, King's College London
Uwe Waldmann, MPI for Informatics
Yoni Zohar, Stanford University

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