Interactive Drama, Art, and Artificial Intelligence

Artificial intelligence methods open up new possibilities in art and entertainment,
enabling rich and deeply interactive experiences. At the same time as AI opens up new
fields of artistic expression, AI-based art itself becomes a fundamental research agenda,
posing and answering novel research questions that would not be raised unless doing AI
research in the context of art and entertainment. I call this agenda, in which AI research
and art mutually inform each other, Expressive AI. Expressive AI takes seriously the
problem of building intelligences that robustly function outside of the lab, engaging
human participants in intellectually and aesthetically satisfying interactions, which,
hopefully, teach us something about ourselves.

This thesis describes a specific AI-based art piece, an interactive drama called
Façade, and describes the practice of Expressive AI, using Façade, as well as additional
AI-based artwork described in the appendices, as case studies.
An interactive drama is a dramatically interesting virtual world inhabited by
computer-controlled characters, within which the player experiences a story from a first
person perspective. Over the past decade, there has been a fair amount of research into
believable agents, that is, autonomous characters exhibiting rich personalities, emotions,
and social interactions. There has been comparatively little work, however, exploring
how the local, reactive behavior of believable agents can be integrated with the more
global, deliberative nature of a story plot, so as to build interactive, dramatic worlds. This
thesis presents Façade, the first published interactive drama system that integrates
character (believable agents), story (drama management) and shallow natural language
processing into a complete system. Façade will be publicly released as a free download
in 2003.

In the Façade architecture, the unit of plot/character integration is the dramatic beat.
In the theory of dramatic writing, beats are the smallest unit of dramatic action, consisting
of a short dialog exchange or small amount of physical action. As architectural entities,
beats organize both the procedural knowledge to accomplish the beat’s dramatic action,
and the declarative knowledge to sequence the beat in an evolving plot. Instead of
conceiving of the characters as strongly autonomous entities that coordinate to
accomplish dramatic action through purely local decision-making, characters are instead
weakly autonomous – the character’s behavioral repertoire dynamically changes as beats
are sequenced. The Façade architecture includes ABL (A Behavior Language), a new
reactive planning language for authoring characters that provides language support for
joint action, and a drama manager consisting of both a language for authoring the
declarative knowledge associated with beats and a runtime system that dynamically
sequences beats.

Façade is a collaboration with independent artist and researcher Andrew Stern.
Expressive AI is not the “mere” application of off-the-shelf AI techniques to art and
entertainment applications. Rather, Expressive AI is a critical technical practice, a way of
doing AI research that reflects on the foundations of AI and changes the way AI is done.
AI has always been in the business of knowing-by-making, exploring what it means to be
human by building systems. Expressive AI just makes this explicit, combining the
thought experiments of the AI researcher with the conceptual and aesthetic experiments
of the artist. As demonstrated through Façade and the other systems/artworks described
in the appendices, combining art and AI, both ways of knowing-by-making, opens up
new research questions, provides a novel perspective on old questions, and enables new
modes of artistic expression. The firm boundary normally separating “art” and “science”
is blurred, becoming two components of a single, integrated practice.

(Source: Author's abstract)