  The purpose of the paper is to introduce a new approach of planning called
Assumption-Based Planning. This approach is a very interesting way to devise a
planner based on a multi-agent system in which the production of a global
shared plan is obtained by conjecture/refutation cycles. Contrary to classical
approaches, our contribution relies on the agents reasoning that leads to the
production of a plan from planning domains. To take into account complex
environments and the partial agents knowledge, we propose to consider the
planning problem as a defeasible reasoning where the agents exchange proposals
and counter-proposals and are able to reason about uncertainty. The
argumentation dialogue between agents must not be viewed as a negotiation
process but as an investigation process in order to build a plan. In this
paper, we focus on the mechanisms that allow an agent to produce `reasonable'
proposals according to its knowledge.
