From 24–30 August 2026, the Faculty of Mathematics and Informatics at Vilnius University (VU MIF) is hosting the international conference and summer school "Declarative AI 2026: Rules, Reasoning, Decisions, and Explanations". The academic event brings together specialists and researchers in artificial intelligence (AI), knowledge representation, logical reasoning and neurosymbolic AI from 5 continents, 22 countries. The Lithuanian Artificial Intelligence Association is contributing to organizing the conference in Lithuania.
"As the use of generative artificial intelligence and large language models grows rapidly, increasing attention is being paid not only to what an AI system can generate, but also to how it reasons, makes decisions, and whether those decisions can be explained, checked, or verified," says one of the conference organizers, Linas Petkevičius, Director of the Institute of Computer Science at VU MIF. "It is precisely these issues that “Declarative AI 2026“ addresses, with topics spanning rule- and logic-based AI, knowledge graphs, ontologies, machine reasoning, neurosymbolic methods, explainable AI, and decision technologies."
The classic use of language models (e.g., ChatGPT) is often free-form in nature – their answers can be imprecise, prone to hallucinations and uncertainty – whereas declarative AI is grounded in logic, clear rules and a systematic approach, producing verifiable, automated processes that guarantee a reliable and consistent result in every case. This approach is especially useful for tackling complex problems that require accounting for numerous rules and possible solution paths.
The conference was opened by Dr Davide Lanti (Free University of Bozen-Bolzano) and Prof. Adrian Paschke (Free University of Berlin)
The week-long event brings together several international initiatives: the RuleML+RR 2026 conference, the 22nd "Reasoning Web" summer school, and DecisionCAMP 2026. The main part of the conference takes place on 24–26 August, while 27–30 August is given over to the "Reasoning Web" summer school, aimed primarily at doctoral students, master's students, postdoctoral researchers and early-career scientists.
Internationally recognised AI scientists in Vilnius
The conference program features talks and lectures covering the most pressing issues in contemporary AI. Among the invited speakers are Thomas Bolander of the Technical University of Denmark, presenting a path from dynamic epistemic logic to socially intelligent robots; Stefania Dumbrava of France, speaking on declarative foundations from graph data to neurosymbolic AI; and Matti Järvisalo of the University of Helsinki, examining the solving of complex optimization problems by combining reasoning and optimization.
Prof. Matti Järvisalo (University of Helsinki)
Hector Geffner, Alexander von Humboldt Professor at RWTH Aachen University, will also give a lecture at the "Reasoning Web" summer school. His lecture addresses the interplay among learning, reasoning, and planning, and the combination of symbolic and neural methods – an area that is becoming increasingly relevant in the search for alternatives to AI systems that rely solely on vast quantities of data.
The conference's scientific program also reflects highly topical themes – from evaluating the logical reasoning abilities of language models and more reliable formalization of language models, to agentic AI, knowledge graphs, rule-based machine learning, and the application of neurosymbolic systems in the energy sector.
Lithuania – not merely a consumer of AI technologies
Hosting "Declarative AI 2026" in Vilnius gives the Lithuanian AI community a direct opportunity to take part in the international discussion on what the next stage of artificial intelligence should look like – more reliable, capable of reasoning, able to explain its decisions, and combining neural and symbolic methods.
VU MIF researchers – Assoc. Prof. Asta Slotkienė, Assoc. Prof. Linas Petkevičius and Prof. Virginijus Marcinkevičius
Representatives of the Lithuanian academic and AI communities are also contributing to the organization of the event. The local organizing committee is chaired by Assoc. Prof. Linas Petkevičius, Director of the Institute of Computer Science at VU MIF, while the RuleML+RR Doctoral Consortium is led by Prof. Virginijus Marcinkevičius of the VU MIF Institute of Data Science and Digital Technologies.
The delivery of "Declarative AI 2026" is also being supported by leaders in the technology industry. NVIDIA and its Lithuanian partner "3RTechnology" have become conference sponsors, contributing to the gathering of the international artificial intelligence community in Vilnius. This partnership strengthens the conference's link between academic AI research and the practical application of cutting-edge technologies, and gives Lithuanian researchers and the technology community greater opportunities to build direct connections with the global AI ecosystem.
24 August 2026
