  In this paper, we propose a single-agent modal logic framework for reasoning
about goal-direct "knowing how" based on ideas from linguistics, philosophy,
modal logic and automated planning. We first define a modal language to express
"I know how to guarantee phi given psi" with a semantics not based on standard
epistemic models but labelled transition systems that represent the agent's
knowledge of his own abilities. A sound and complete proof system is given to
capture the valid reasoning patterns about "knowing how" where the most
important axiom suggests its compositional nature.
