Workshop on Admissible Rules and Unification III

May 11 — 12, 2019

Programme   Venue & Local Info

Admissible rules of a logical system are rules that can be added to the system without changing its set of theorems. In algebra, admissible rules correspond to quasi-equations holding in free algebras, while from a computer science perspective, admissibility is intimately related to equational unification. The aim of this workshop is to bring together experts from these distinct areas of research spanning mathematics, philosophy, and computer science, to share ideas and methods. Previous editions of the workshop were held in Utrecht (2011), and in Les Diablerets (2015). Everybody is welcome to attend the workshop. Giving a talk and attending the conference dinner is by invitation only.
To contact the organization, please send an email to

Thank you for coming and see you in the next edition!

Important Dates

Workshop: Prague, 11 - 12 May 2019
Welcome party: 10th May 2019 at the venue of the workshop
Social dinner: 11th May 2019

Conference Programme

A welcome party will be held at 19:00 of the 10th May. See Social Programme .

Saturday 11th Sunday 12th
9:00 -
Zuzana Haniková
Structural completeness in MV and Product algebras with rational constants
9:30 -
FROM 9:50h: OPENING Sam van Gool
Equations and logic on words
Franz Baader
Unification modulo TBoxes aka Global Consequence aka Ground Identities
Nick Bezhanishvili
Citkin's characterization of hereditarily structurally complete intermediate logics via Esakia duality
10:30 -
Wojciech Dzik
Applications of Second-order Unification
in Superintuitionistic Predicate Logics.

Coffee Break

11:00 -

Coffee Break

Adam Přenosil
Antistructural completeness and inconsistency lemmas
11:30 -
Alex Citkin
Hereditarily structurally complete implication-
disjunction fragments of intermediate logics
Michal M. Stronkowski
(Active) Structural completeness for
tabular modal logics
12:00 -
Rosalie Iemhoff
The Skolem Class of Intermediate Logics
Tommaso Moraschini
Singly generated quasivarieties and passive structural completeness
12:30 -

Lunch break

15:30 -
Amirhossein Akbar Tabatabai
On the Existence of the Sequent-style Proof Systems
16:00 -
Raheleh Jalali
Uniform Interpolation for Semi-analytic Proof Systems
16:30 -


17:00 -
George Metcalfe
Checking Admissibility using Natural Dualities




WARU will be held at the Institute of Philosophy of the Czech Academy of Sciences, located in Jilská 1, Praha 1 – Staré Město, in the very center of Prague's old town. The nearest subway station is Národní třída (line B).
Lecture rooms will be equipped with a data projector. It is advised to have your presentation prepared in .pdf on a USB key.

Social Programme

A welcome party will be held at 19:00 of the 10th May 2019 at the venue of the workshop. The event is joint with Prague Gathering of Logicians 2019.
Social dinner will be held at 19:00 on May 11th, at the restaurant U Bulínů (Budečská 803/2, Prague 2). The costs of the dinner are not covered by the organization. The meeting point will be in front of the venue at 18:30. To get to the restaurant we will take tram 22 from Národní třída to Jana Masaryka. Tram tickets will be provided by the organizers.

Related Events

There are two other logic-related events happening in Prague just before WARU.
Prague Gathering of Logicians, held on 9 and 10th of May. It is an annual meeting of researchers in logic and related disciplines, mostly based in the Czech Republic.
Prague Logc Camp, held on 6-9 May. It is a spring school/workshop for early career researchers in logic.

Local information

Local currency and exchange rates
The currency in the Czech Republic is the Czech crown (CZK or Kč).
1 EUR = approx. 25 CZK
1 USD = approx. 22 CZK
We advise you not to change money at the airport; use the ATMs instead. Later in town you can exchange money at much better rates, ATMs are omnipresent, and card acceptance is almost universal. It is advisable, however, to have enough cash when going to restaurants, cafes etc. as these do not always accept cards.

Public transportation in Prague
Prague public transportation is integrated, tickets are valid on all forms of public transport. The tickets must be bought in advance. They are sold at tobacconists, newsagents and from the ticket machines (usually coins only) located at the metro stations and elsewhere. There is also a special booth at the airport Terminal 2. On buses and trams you must punch your ticket immediately after getting on. At the metro, the ticket must be marked at the entrance. There are two kind of tickets: 24 CZK (valid for 30 min) and 32 CZK (valid for 90 min). 24 and 72 hour tickets are also available for 110 CZK or 310 CZK, respectively (there is no weekly ticket). For detailed information about the fares and connections available see or

Transit from/to the airport
Bus 119 connects Nádraží Veleslavín metro station (line A) with the airport. The bus stop is right in front of the arrivals hall and the journey takes less than 20 minutes. From Nádraží Veleslavín you can continue to the center by subway. The standard ticket is valid for this bus (and the consecutive subway ride modulo the time restrictions mentioned above; we advise to validate the 90 min ticket for the ride to/from your hotel). Bus AE (Airport express) connects the airport with main railway station (Hlavní nádraží). The standard ticket is not valid on this bus (this together with the funicular in the ZOO are the only two exceptions of the general rule mentioned above). The special ticket costs 60 CZK and is sold by the bus driver. More information about transport from/to the airport by public transport can be found at General tourist information about Prague can be found at

Arriving to Prague by train or bus
The main railway station (Hlavní nádraží) is located in the city centre, on subway line C. The tram stop is located to the right of the main exit behind a park. The main bus station (Florenc) is located near the main railway station, also on subway line C.

Prices and tipping
The usual price for a full lunch or dinner at a restaurant is 150–300 CZK, a coffee costs 30–60 CZK. Service is usually not included in the bill. If you wish to tip, it is customary to give extra 10%.


The meeting is co-organized by the Institute of Philosophy, and the Institute of Computer Science
of the Czech Academy of Sciences.

Programme Committee

Petr Cintula, Rosalie Iemhoff, George Metcalfe, Tommaso Moraschini (Chair)

Organizing Committee

Tommaso Moraschini (Chair), Vítek Punčochář, Amanda Vidal

This event received funds from the The Czech Society for Cybernetics and Informatics