A tutorial at IJCAI 2019, August 10 - August 16, Macau, China

The AI Universe of “Actions”: Agency, Causality, Commonsense and Deception

by Chitta Baral and Tran Cao Son



Actions have played an important role in AI from its early days starting from their use in McCarthy’s Situation calculus and in AI planning; but more recently actions have played a crucial role in Pearl’s formulations of causal reasoning and do-calculus, in understanding and acquiring action-centric commonsense knowledge, and in dealing with knowledge goals, such as deception, in multi-agent scenarios.

In this tutorial we will cover the story of action and change from Heraclitus’ doctrine (540 BC-480 BC) that “all things are in constant flux”, to its role in the early days of AI and through the development of action languages, and the recent developments with respect to multi-agency, causality, commonsense and deception. We will connect all of these so that various researchers working on particular aspects of actions become aware of the broader picture, thus enhancing the research landscape.



  1. Overview: a brief history of action languages 
  2. Action languages in single agent environments
    1. The action language A, state, and transition function 
    2. Extension of A domains with static causal laws, non-deterministic actions, and sensing actions 
    3. Golog 
  3. Action languages and causality 
    1. Pearl’s do-calculus 
    2. Relationship between Pearl’s do-calculus and action languages 
  4. Action languages in multi-agent environments
    1. Action language mA*, Kripke structure, update models, and transition function 
    2. mA* in epistemic planning 
  5. Action languages in commonsense reasoning
    1. Commonsense reasoning and actions 
    2. The knowledge acquisition task and actions 
  6. Open challenges, conclusion, and discussion


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