  Conversational agents, also known as chatbots, are versatile tools that have
the potential of being used in dialogical argumentation. They could possibly be
deployed in tasks such as persuasion for behaviour change (e.g. persuading
people to eat more fruit, to take regular exercise, etc.) However, to achieve
this, there is a need to develop methods for acquiring appropriate arguments
and counterargument that reflect both sides of the discussion. For instance, to
persuade someone to do regular exercise, the chatbot needs to know
counterarguments that the user might have for not doing exercise. To address
this need, we present methods for acquiring arguments and counterarguments, and
importantly, meta-level information that can be useful for deciding when
arguments can be used during an argumentation dialogue. We evaluate these
methods in studies with participants and show how harnessing these methods in a
chatbot can make it more persuasive.
