  Propositional Dynamic Logic or PDL was invented as a logic for reasoning
about regular programming constructs. We propose a new perspective on PDL as a
multi-agent strategic logic (MASL). This logic for strategic reasoning has
group strategies as first class citizens, and brings game logic closer to
standard modal logic. We demonstrate that MASL can express key notions of game
theory, social choice theory and voting theory in a natural way, we give a
sound and complete proof system for MASL, and we show that MASL encodes
coalition logic. Next, we extend the language to epistemic multi-agent
strategic logic (EMASL), we give examples of what it can express, we propose to
use it for posing new questions in epistemic social choice theory, and we give
a calculus for reasoning about a natural class of epistemic game models. We end
by listing avenues for future research and by tracing connections to a number
of other logics for reasoning about strategies.
