Toward Characters Who Observe, Tell, Misremember, and Lie

Abstract

Knowledge and its attendant phenomena are central to human storytelling and to the human experience more generally, but we find very few games that revolve around these concerns. This works to preclude a whole class of narrative experiences in games, and it also damages character believability. In this paper, we present an AI framework that supports gameplay with non-player characters who observe and form knowledge about the world, propagate knowledge to other characters, misremember and forget knowledge, and lie. We outline this framework through the lens of a gameplay experience that is intended to showcase it, called Talk of the Town, which we are currently developing. From a review of earlier projects, we find that our system has a novel combination of features found only independently across other systems, and that it is among the first to support character memory fallibility.

Computatrum Personae: Toward a Role-Based Taxonomy of (Computationally Assisted) Performance

“…• Bad News: A world generator (Ryan et al 2015) simulates 150 years of history of a small American town. Players explore this town, engaging in conversations with NPCs that are portrayed by a human improvisational actor.…”

Playable Experiences at AIIDE 2016

“…Beyond its novelty, this work is deeply AI-driven. Each Bad News town is procedurally generated using the Talk of the Town AI framework (Ryan et al 2015b). Specifically, towns are simulated for 140 years of diegetic time, yielding hundreds of residents who are so-Figure 7: Bad News: Excerpt from a business directory for a procedurally generated town, as displayed on the player interface.…”

Dynamic Epistemic Logic in Game Design

“…The game on which Juke Joint is based, "Talk of the Town" (Ryan et al 2015), is also remarkable due to its extensive treatment of belief dynamics in characters. These dynamics are varied (propagation, fabrication, misremem-brance…), but the contents of the beliefs will not be reflected upon or used in reasoning further than eliciting a certain appraisal.…”

“…Making a mental model of the other agent's mind and reproducing their reasoning is crucial both to detect a lie and to lie successfully, a kind of agent behavior that is not well explored in games. Although it is already implemented in a game mentioned above (Ryan et al 2015), a more detailed description of the goals and mechanisms of lying as a way of manipulating another agent was described by Henrique Reis (Reis 2012), although we think the mechanisms used were not appropriate for the task. A formal approach to this human characteristic has been described in the context of DEL (van Ditmarsch et al 2012), also linking it to game theory.…”