ABSTRACT
Action failure is tied to different types of incompleteness. The conjecture advanced is this: if the multifaceted phenomenon of action incompleteness is to be accounted for, then a proposition defining the type sensitivity of action tokens should be taken as the starting point for structuring the syntax of a modal logic of action. Action incompleteness may become an issue in developing a dynamic logic of action by way of setting an axiomatic basis for the operator δ, which has been used in K. Segerberg with intuitive reading "bringing it about". The maximality principle can be interpreted to mean that running a specific routine is the proper way to achieve a proposed action goal. Galilean Relativity or Invariance comes with a fundamental insight into the radical contingency of action: forces do not act directly on systems, but always on parts of them. An example taken from literature may further illustrate the third type of action incompleteness.
