The Tenth Scandinavian Logic Symposium
The Tenth Scandinavian Logic Symposium (SLS 2018) was held at the University of Gothenburg, Sweden during June 1113, 2018, under the auspices of the Scandinavian Logic Society. The previous two meetings of the SLS were held in Tampere, Finland (2014) and Roskilde, Denmark (2012).
The primary aim of the Symposium is to promote research in the field of logic (broadly conceived) carried out in research communities in Scandinavia. Moreover, it warmly invites participation of logicians from all over the world. The meeting will include invited lectures and a forum for participants to present contributed talks.
The scope of this event covers mathematical, computational, and philosophical logic. The major topics include (but are not limited to) the areas of Proof Theory, Constructivism, Model Theory, Set Theory, Computability Theory, Algebra and Logic, Categorical Logic, Logic and Computer Science, Logic and Linguistics, Logic in AI and MultiAgent Systems, Logics of Games, Modal and other nonclassical Logics, Axiomatic Theories of Truth, and Philosophical Logic.
We are proud to announce that the 2018 Lindström Lectures will be a part of SLS 2018 and delivered by Michael Rathjen. For more information see Lindström lectures webpage.
SLS 2018 is collocated with the Workshop on Dialogue and Perception 2018, June 1415, 2018.
Important dates
 Abstract deadline:
April 1, 2018Extended to: April 8, 2018.  Notification: April 20, 2018
 Early registration deadline: May 1, 2018
 Main event: June 1113, 2018
Content
 Speakers
 Schedule
 Registration
 Submit an abstract
 Conference dinner
 Information and venue
 Organization and sponsors
Speakers
Invited speakers:

Joel David Hamkins (CUNY): Settheoretic potentialism and the universal finite set
Providing a settheoretic analogue of the universal algorithm, I shall define a certain finite set in set theory {x  φ(x)} and prove that it exhibits a universal extension property: it can be any desired particular finite set in the right settheoretic universe and it can become successively any desired larger finite set in topextensions of that universe. Specifically, ZFC proves the set is finite; the definition φ has complexity Σ₂ and therefore any instance of it φ(x) is locally verifiable inside any sufficiently large V~θ~; the set is empty in any transitive model; and if φ defines the set y in some countable model M of ZFC and y ⊂ z for some finite set z in M, then there is a topextension of M to a model N of ZFC in which φ(x) defines the new set z. I shall draw out consequences of the universal finite set for settheoretic potentialism and discuss several issues it raises in the philosophy of set theory.
The talk will include joint work with W. Hugh Woodin, Øystein Linnebo and others. Questions and commentary concerning the talk can be made at: http://jdh.hamkins.org/settheoreticpotentialismsls2018. 
Luke Ong (Oxford): Higherorder constrained Horn clauses and automatic program verification
We introduce constrained Horn clauses in higherorder logic, and study satisfiability and related decision problems motivated by the automatic verification of higherorder programs. Although satisfiable systems of higherorder clauses in the standard semantics do not generally have least models, by viewing these systems as a kind of monotone logic programs, we show that there are nonstandard semantics that do satisfy the least model property. Moreover the respective satisfiability problems in the standard and nonstandard semantics are interreducible. With a view to exploiting the remarkable efficiency of SMT solvers, we survey recent developments in the algorithmic solution of higherorder Horn systems by reduction to first order, and discuss related problems. 
Michael Rathjen (Leeds) Public Lindström Lecture on Monday: Progressions of theories and slow consistency
The fact that “natural” theories, i.e. theories which have something like an “idea” to them, are almost always linearly ordered with regard to logical strength has been called one of the great mysteries of the foundation of mathematics. Using paradoxical methods, e.g. selfreference Rosserstyle, one can distill theories with incomparable logical strengths and show that the degree structure of logical strengths is dense in that between two theories S < T one can always find a third Q such that S < Q < T . But are there “natural” examples of such phenomena? We also know how to produce a stronger theory by adding the consistency of the theory. Can we get a stronger theory by adding something weaker than consistency that is still “natural”? These and other questions will be broached in the talk. 
Michael Rathjen (Leeds) Research Lindström Lecture on Wednesday: Bounds for the strength of the graph minor and the immersion theorem
The graph minor theorem, GM, is arguably the most important theorem of graph theory. The strength of GM exceeds that of the standard classification systems of RM known as the “big five”. The plan is to survey the current knowledge about the strength of GM and other Kruskallike principles, presenting lower and upper bounds. 
Katrin Tent (Münster): Ampleness in strongly minimal structures
The notion of ampleness captures essential properties of projective spaces over fields. It is natural to ask whether any sufficiently ample strongly minimal set arises from an algebraically closed field. In this talk I will explain the question and survey recent results on ample strongly minimal structures.
The programme and book of abstracts is available as a pdf.
Schedule
The schedule for the symposium is available as a pdf.
Registration
To register please use the registration form. Please note that if a Swedish university is paying the registration fee you should not pay the VAT.
After you have registered you need to pay through the payment site. Please use the exact same name when paying as you used to register.
Early registration fees, applicable until 1st May, are:
 Regular fee (incl. VAT). 600 SEK
 Regular fee (excl. VAT). 480 SEK
 Student fee (incl. VAT). 400 SEK
 Student fee (excl. VAT). 320 SEK
Late fees will be announced later. If you need more information please contact the organisers.
Submit an abstract
Abstracts of contributed talks must be submitted as pdf files via EasyChair: https://easychair.org/conferences/?conf=sls2018
The abstracts should be prepared according to the ASL abstract guidelines: http://www.aslonline.org/rules_abstracts.html.
Upon notification of acceptance, authors will be requested to submit the LaTeX source files.
Conference dinner
The dinner will be held at Villa Belparc located in the beautiful park Slottskogen right by the Botanical Gardens.
 Dinner fee (incl. VAT). 700 SEK
 Dinner fee (excl. VAT). 600 SEK
Information and venue
The conference will be held at Eklandagatan 86, once the home of the Maths department and now housing the Department of History. It’s located close to Chalmers Johanneberg campus and a short bus trip (or a 20 minute walk) from Korsvägen – the first stop of the airport coaches.
We recommend the nearby located Quality Hotel Panorama.
Please see the map with the venue, hotel, lunch places and bus stops marked.
Organization and sponsors
Programme and organizing committee:
 Bahareh Afshari (cochair)
 Rasmus Blanck
 Ali Enayat (cochair)
 Fredrik Engström
 Martin Kaså
 Graham Leigh
For enquiries please email: sls2018 at flov.gu.se
Sponsors:
 Association for Symbolic Logic
 Department of Philosophy, Linguistics and Theory of Science (University of Gothenburg)
 Knut and Alice Wallenberg Foundation
 WennerGren Stiftelserna