$5HIOH[LYH1RW,PSXOVLYH$JHQW &DWKHULQH3HODFKDXG 'LSDUWLPHQWRGL,QIRUPDWLFDH 6LVWHPLVWLFD 8QLYHUVLWjGL5RPD³/D6DSLHQ]D´ FDWK#GLVXQLURPDLW ,VDEHOOD3RJJL 'LSDUWLPHQWRGL/LQJXLVWLFD 8QLYHUVLWjGL5RPD SRJJL#XQLURPDLW %HUDUGLQD'H&DUROLVDQG )LRUHOODGH5RVLV 'LSDUWLPHQWRGL,QIRUPDWLFD 8QLYHUVLWjGL%DUL ^GHFDUROLV_GHURVLV`#GLXQLEDLW ABSTRACT The aim of our present research is to build an Agent capable of communicative and expressive behavior. The Agent should be able to express its emotions but also to refrain from expressing them: a reflexive, not an impulsive Agent. A Reflexive Agent is an agent who thinks it over before displaying one’s emotions, that is, one who, when feeling an emotion, “decides” not to display it immediately. In this paper we present our enriched discourse generator and we give a general overview of the factors that we consider to determine the displaying or not displaying of an emotion. 1. INTRODUCTION Up to now, Artificial Agents are not yet endowed with the capacity of feeling emotions, mainly because emotion would imply an involvement of the hardware of a machine; and this might be impossible, or at least difficult, still for some years [6]. But let us suppose we have an Agent that is able to feel emotions; what could it do? How could it behave? Would it express its emotion to a potential interlocutor, or would it ruminate on its own emotion by itself, without showing its feeling? The aim of our research is to build an Agent that is able to express its emotions but also to refrain from expressing them: a reflexive, not an impulsive Agent. In this paper we present a general overview of the factors that affect the displaying of one’s emotion or not. 2. EMOTION TRIGGERING FACTORS Emotions, as we know, are a biological feed-back device whose function is to provide information about the state of achievement or thwarting of our most important adaptive goals. Every time a relevant event happens in the environment (or is simply assumed to happen by a System), due to which an important goal of the System (the goal of survival, bodily safety, reproduction, image or self-image) is, or is likely to be, achieved or thwarted, the feed-back device of Emotion is activated; this consists of a set of somatic, physiological, psychological, expressive and motivational issues that alert the System and, at the same time, provide the necessary energy and resources for reaction. From the agent’s interpretation of the situation, an emotion is triggered. We use emotion types as defined in Elliott’s Affective Reasoner, in which 24 emotions are described [3]. 3. EMOTION REGULATION FACTORS Now, the expressive part of the emotional reaction (the fact, for example, that we open eyes wide in fear, or make a frown in anger, or blush in shame) usually has a useful adaptive function. For example, showing my rival I am angry with him may induce him to leave the field. Sometimes, though, expressing our emotion may be dangerous rather than useful. If I show fear in front of a rival, this may give him a weapon and may oblige me to leave the field. Humans, then, learned to be flexible in the use of the expressive part of the Emotion syndrome: that we are biologically endowed with a repertoire of display devices does not necessarily mean that, any time we feel an emotion we immediately, coercively and unthoughtfully, display that emotion. In fact, a famous elaboration around this topic is Ekman and Friesen’s [2] notion of display rules: the rules prescripted by cultures about when, how, to whom express one’s emotions. What we are trying to do in our work is to propose a formalization of some of these rules. We start from the following question: what are the factors that determine if an Agent that is feeling an emotion will display it or not? In our view, this depends on two aspects of the emotion: on the one side, whether and how to display an emotion depends on the very nature of the emotion itself (emotional nature); on the other side, it is determined by the interaction of multiple factors (scenario factors). 1. Emotional nature 1.1. Emotion valence: Emotions may be either positive or negative, in that feeling them may be pleasant or unpleasant. 1.2. Emotion social evaluation: Emotions may be socially approved or sanctioned. The latest ones are much less proned to be displayed (e.g envy, shame). 1.3. Emotion Addressee: Among social emotions, some may directed toward the interlocutor or toward a third person. It might be easier for me to say I contempt a third person than I contempt you. 2. Scenario Factors 2.1. Agent’s Display motive: There might be several reasons one displayed an emotion. One may look for consolation, empathy, advice… We call display motive the reason (that is the specific goal) that induces us to display a particular emotion in a particular situation. Permission to make digital or hard copies of all or part of this work for personal or classroom use is granted without fee provided that copies are not made or distributed for profit or commercial advantage and that copies bear this notice and the full citation on the first page. To copy otherwise, or republish, to post on servers or to redistribute to lists, requires prior specific permission and/or a fee. AGENTS’01, May 28-June 1, 2001, Montréal, Québec, Canada. Copyright 2001 ACM 1-58113-326-X/01/0005…$5.00. 186