"It's about thinking. The main theory is that emotions are nothing special. Each emotional state is a different style of thinking. So it's not a general theory of emotions, because the main idea is that each of the major emotions is quite different. They have different management organizations for how you are thinking you will proceed."
- Marvin Minsky

"[Joshua] Greene's data builds on evidence suggesting that psychopaths suffer from a severe emotional disorder -- that they can't think properly because they can't feel properly.'This lack of emotion is what causes the dangerous behavior,' said James Blair, a cognitive psychologist at the National Institute of Mental Health."
- from Hearts & Mind. The Boston Globe (April 29, 2007)

Hearts & Minds - Since Plato, scholars have drawn a clear distinction between thinking and feeling. Now science suggests that our emotions are what make thought possible. By Jonah Lehrer. The Boston Globe (April 29, 2007). "Just over 50 years ago, a group of brash young scholars at an MIT symposium introduced a series of ideas that would forever alter the way we think about how we think. In three groundbreaking papers, including one on grammar by a 27-year-old linguist named Noam Chomsky, the scholars ignited what is now known as the cognitive revolution, which was built on the radical notion that it is possible to study, with scientific precision, the actual processes of thought. The movement eventually freed psychology from the grip of behaviorism, a scientific movement popular in America that studied behavior as a proxy for understanding the mind. ... 'Because we subscribed to this false ideal of rational, logical thought, we diminished the importance of everything else,' said Marvin Minsky, a professor at MIT and pioneer of artificial intelligence. 'Seeing our emotions as distinct from thinking was really quite disastrous.' ... From its inception, the cognitive revolution was guided by a metaphor: the mind is like a computer. We are a set of software programs running on 3 pounds of neural hardware. And cognitive psychologists were interested in the software. The computer metaphor helped stimulate some crucial scientific breakthroughs. It led to the birth of artificial intelligence and helped make our inner life a subject suitable for science. For the first time, cognitive psychologists were able to simulate aspects of human thought. At the seminal MIT symposium, held on Sept. 11, 1956, Herbert Simon and Allen Newell announced that they had invented a 'thinking machine' -- basically a room full of vacuum tubes -- capable of solving difficult logical problems. (In one instance, the machine even improved on the work of Bertrand Russell.) ... But the computer metaphor was misleading, at least in one crucial respect. Computers don't have feelings. Feelings didn't fit into the preferred language of thought. Because our emotions weren't reducible to bits of information or logical structures, cognitive psychologists diminished their importance. ... This new science of emotion has brought a new conception of what it means to think, and, in some sense, a rediscovery of the unconscious. ... The lasting influence of the cognitive revolution is apparent in the language used by neuroscientists when describing the mind. For example, the unconscious is often described as a massive computer, processing millions of bits of information per second. Emotions emerge from this activity."

The Love Machine - Building computers that care. By David Diamond. Wired Magazine (December 2003). "[Tim] Bickmore's area of study is called affective computing. Its proponents believe computers should be designed to recognize, express, and influence emotion in users. Rosalind Picard, a genial MIT professor, is the field's godmother; her 1997 book, Affective Computing, triggered an explosion of interest in the emotional side of computers and their users. ... And she developed an interest in the work of neuroscientist Antonio Damasio. In his 1994 book, Descartes' Error , Damasio argued that, thanks to the interplay of the brain's frontal lobe and limbic systems, our ability to reason depends in part on our ability to feel emotion. Too little, like too much, triggersbad decisions. The simplest example: It's an emotion - fear - that governs your decision not to dive into a pool of crocodiles."''

Watch this talk by Rosalind Picard, Media Laboratory, Massachusetts Institute of Technology: Machines with Emotional Intelligence. From The University of Washington Computer Science & Engineering Colloquium Series, CSE Colloquia - 2001."This program will describe how we're giving computers some social skills, specifically the ability to recognize and respond appropriately to human emotion."

• See these other videos from the AAAI Video Archive that have "emotion" as one of the tags.

Emotion. By Ronald de Sousa. Entry in the Stanford Encyclopedia of Philosophy. "[S]ome philosophers and computer scientists have continued to be interested in integrating computing theory with emotions. Aaron Sloman has elaborated the sort of ideas that were embryonic in Shank and Colby into a more sophisticated computational theory of the mind in which emotions are virtual machines, playing a crucial role in a complex hierarchic architecture in which they control, monitor, schedule and sometimes disrupt other control modules. (Wright, Sloman & Beaudoin 1996). Rosalind Picard (1997) lays out the evidence for the view that computers will need emotions to be truly intelligent, and in particular to interact intelligently with humans. She also adverts to the role of emotions in evaluation and the pruning of search spaces. But she is as much or more concerned to provide an emotional theory of computation than to elaborate a computational theory of emotions. Lastly, a forthcoming book by Marvin Minsky bears the promising title of The emotion machine."

A Human Touch for Machines - The radical movement of affective computing is turning the field of artificial intelligence upside down by adding emotion to the equation. By Charels Piller. Los Angeles Times (May 7, 2002). "For the last decade, the UC San Diego psychologist has traveled a quixotic path in search of the next evolutionary leap in computer development: training machines to comprehend the deeply human mystery of what we feel. [Javier ] Movellan's devices now can identify hundreds of ways faces show joy, anger, sadness and other emotions. The computers, which operate by recognizing patterns learned from a multitude of images, eventually will be able to detect millions of expressions. ... Such computers are the beginnings of a radical movement known as 'affective computing.' The goal is to reshape the very notion of machine intelligence. ... Such devices may never replicate human emotional experience. But if their developers are correct, even modest emotional talents would change machines from data-crunching savants into perceptive actors in human society. At stake are multibillion-dollar markets for electronic tutors, robots, advisors and even psychotherapy assistants. ... Classical AI researchers model the mind through the brute force of infinite logical calculations. But they falter at humanity's fundamental motivations. ... Movellan is part of a growing network of scientists working to disprove long-held assumptions that computers are, by nature, logical geniuses but emotional dunces. ... Scientists don't foresee machines with Hal's emotional skills--or, fortunately, its malevolence--soon. But they already have debunked AI orthodoxy considered sacrosanct only five years ago--that logic is the one path to machine intelligence. It took psychologists and neuroscientists--outside the computer priesthood--to see inherent limits in the mathematical pursuit of intelligence that has dominated computer science."

• Visit the Machine Perception Laboratory at the University of California, San Diego and see projects such as Fully Automatic Recognition of Expressions of Basic Emotion.

Emotion and Affect - An interview with Don Norman. Ubiquity (Issue 13: May 14-20, 2002). "UBIQUITY: Talk about your work with robots. NORMAN: I became interested in the design of robots, which will be a theme of the book, as well. The question is, how do you make a home robot that is autonomous, that lives by itself, that won't get stuck in corners, and doesn't have to be reminded so that it doesn't run out of power? I decided that what it needed was emotions, or affect. UBIQUITY: What kinds of emotions? NORMAN: It had to get frustrated. Being frustrated gets it out of deadlocks. If it's stuck somewhere trapped in a corner, it has intelligent algorithms trying to get it out. But if they fail, it says, 'the hell with it,' and goes off and does something else. It should be afraid of heights so that it doesn't fall down the stairs. It should get fatigued so that it won't wear out the battery. As its battery level gets lower, it should travel more slowly and not do some tasks. It should always make sure its close enough to the recharging station so that it can get back. UBIQUITY: But are those emotions not essentially algorithms? NORMAN: So what is an emotion? ..."

Films Such as 'I, Robot' Affirm Human Superiority. Duke News & Communications (July 14, 2004). "'I, Robot,' which opens Friday, revisits one of science fiction's common themes: A creation that develops a will of its own and turns against its creator. But why is that idea so appealing? It speaks to our society's deep fears that, as robots become more apparently human, we discover how machinelike we are, said Priscilla Wald, a Duke University English professor who studies how science is represented in popular culture. ... People feel anxious when they learn how easy it is to program a computer to appear to have emotions. This is possible because we follow predictable patterns, she said. 'Our sense of our uniqueness is threatened by the idea that we are predictable,' she said. 'The farther we go with artificial intelligence and the more human our machines become, the more we understand how machinelike we are. Many people find that deeply disturbing.'"

Toward Empathetic Agents in Tutoring Systems. By Jessica Faivre, Roger Nkambou, and Claude Frasson. 2003. In Proceedings of the Sixteenth International Florida Artificial Intelligence Research Society Conference, 161-165. Menlo Park, Calif.: AAAI Press. Abstract: "This paper presents a way of improving computerbased with lifelike presence in learning environment. The approach combines Intelligent Tutoring Systems with research on human emotion in Cognitive Sciences, Psychology and Communication. Considering the relations between emotion, cognition and action in contextual learning, we propose an architecture of a multiagent-based instructional system in which two adaptive emotional agents have been integrated. One manifests the tutor's emotional expressions trough a 3D embodied agent, whereas the second is designed to elicit and analyse the learner's emotional experiences during the interactions with the system. We present here the system's architecture and its first implementation."

Why Machines Should Fear - Once a curmudgeonly champion of "usable" design, cognitive scientist Donald A. Norman argues that future machines will need emotions to be truly dependable. By W. Wayt Gibbs. Scientific American (January 2004). "'The cognitive sciences grew up studying cognition--rational, logical thought,' he notes. Norman himself participated in the birth of the field, joining a program in mathematical psychology at the University of Pennsylvania and later helping to launch the human information­processing department (now cognitive science) at the University of California at San Diego. 'Emotion was traditionally ignored as some leftover from our animal heritage,' he says.' 'It turns out that's not true. We now know, for example, that people who have suffered damage to the prefrontal lobes so that they can no longer show emotions are very intelligent and sensible, but they cannot make decisions.' Although such damage is rare, and he cites little other scientific evidence, Norman concludes that 'emotion, or 'affect,' is an information processing system, similar to but distinct from cognition. With cognition we understand and interpret the world--which takes time,' he says. 'Emotion works much more quickly, and its role is to make judgments--this is good, that is bad, this is safe.' ... 'I'm not saying that we should try to copy human emotions,' Norman elaborates. 'But machines should have emotions for the same reason that people do: to keep them safe, make them curious and help them to learn.' Autonomous robots, from vacuum cleaners to Mars explorers, need to deal with unexpected problems that cannot be solved by hard-coded algorithms, he argues."

An Emotional Cat Robot. By Duncan Graham-Rowe. Technology Review (July 26, 2007). "Scientists in the Netherlands are endowing a robotic cat with a set of logical rules for emotions. They believe that by introducing emotional variables to the decision-making process, they should be able to create more-natural human and computer interactions. 'We don't really believe that computers can have emotions, but we see that emotions have a certain function in human practical reasoning,' says Mehdi Dastani, an artificial-intelligence researcher at Utrecht University, in the Netherlands. By bestowing intelligent agents with similar emotions, researchers hope that robots can then emulate this humanlike reasoning, he says. ... In addition to improving interactions, this emotional logic should also help intelligent agents carrying out noninteractive tasks.... 'It's a heuristic that can help make rational decision-making processes more realistic and much more computable,' says Dastani. ... Other robots have been designed to mimic human expressions. But Dastani's focus on how emotions might affect decision makes it different from many of the other projects on emotional, or affective, computing, such as MIT's Kismet robot, developed by Cynthia Breazeal. With Kismet, like other affective robots, the focus is on how to get the robot to express emotions and elicit them from people."

Why you should buy an emotional planner. By Jonathan Gratch. In Proceedings of the Agents'99 Workshop on Emotion-based Agent Architectures (EBAA '99).

• Additional papers about emotion from Jonathan Gratch, Co-DirectorUSC Computational Emotion Group.

The emotional machine. An Interview by Suzy Hansen. Salon.com (January 2, 2002). "Steve Grand, designer of the artificial life program Creatures, talks about the stupidity of computers, the role of desire in intelligence and the coming revolution in what it means to be 'alive.' ... 'But 'Star Trek' has more or less demonstrated that Mr. Spock isn't always as bright as he looks. It's Captain Kirk who always comes out on top because he's got emotions and common sense and all these other things that Spock doesn't have.'"

Interfacing Emotional Behavior Moderators with Intelligent Synthetic Forces. By Randolph M. Jones, Amy E. Henninger and Eric Chown. Presented at the 11th CGF-BR Conference (May 7, 2002) and made available via a link from Soar Technology's Cognitive Research & Architectures page. "The intent of the project is to investigate improved realism in generating complex human-like behavior that is sensitive to emotional assessments related to fear, anger, joy, etc. The emotions model comes from a connectionist cognitive architecture called SESAME, which has been used to model a wide range of human behaviors, including navigation in large-scale spaces and the effects of emotions on learning. The synthetic force model is based on a special operations forces model that is implemented within the Soar architecture for cognition. This paper focuses on the interfaces required to integrate behavior moderators (represented by sub symbolic signalprocessing systems) with higher cognitive processes (represented in a symbol-processing reasoning system)."

Warm and Fuzzy Logic. By Peter Kupfer. Metropolis Magazine (July 2000). "The idea of giving computers personality or, more accurately 'emotional intelligence' may seem creepy, but technologists say that such machines would offer important advantages."

Machine rage is dead ... long live emotional computing. Consoles and robots detect and respond to users' feelings. By Robin McKie. The Observer (April 11, 2004). "Computer angst - now a universal feature of modern life - is an expensive business. But the days of the unfeeling, infuriating machine will soon be over. Thanks to break throughs in AI (artificial intelligence), psychology, electronics and other research fields, scientists are now creating computers and robots that can detect, and respond to, users' feelings. ... A key breakthrough has been the discovery that cool, unemotional decision-making is not necessarily a desirable attribute. In fact, humans cannot make decisions unless they are emotionally involved. 'The cold, unemotional Mr Spock on Star Trek simply could not have evolved,' said artificial intelligence expert Professor Ruth Aylett of Salford University, another Humaine project leader."

The Emotion Machine. By Marvin Minsky. Simon & Schuster (2006).

• Minsky talks about life, love in the age of artificial intelligence. By Carey Goldberg. The Boston Globe (December 4, 2006). "After 20 years of publishing silence, he has just come out with a new book. Called 'The Emotion Machine,' it argues that, contrary to popular conception, emotions aren't distinct from rational thought; rather, they are simply another way of thinking, one that computers could perform. He spoke with Globe reporter Carey Goldberg.Q So here you are, a pioneer of artificial intelligence, writing a book about emotions. What's going on? ..."
• The draft can be accessed via links in the Some Publications section of his home page.
  • The Emotion Machine Architecture, one of the Architectures for Commonsense Reasoning projects at Commonsense Computing @ Media [the MIT Media Lab]. "We are developing a theory about the architecture of commonsense thinking. The design is described most fully in Marvin Minsky's forthcoming book The Emotion Machine, a sequel to The Society of Mind."
    • Also see this related lab project: The Panalogy Reasoning Engine- "We are developing the Panalogy Reasoning Engine, intended as one instance of the Emotion Machine Architecture that places a special emphasize on reflective analogical reasoning using multiple representations. (This is Push Singh's Ph.D. dissertation.)"
    • Also see this interview: Marvin Minsky on Common Sense and Computers That Emote - As artificial intelligence research celebrates its 50th birthday, the MIT icon asks what makes the minds of three-year-olds tick. By Wade Roush. Technology Review (July 13, 2006). "TR: What are some of the main arguments or research recommendations in your upcoming book, The Emotion Machine?MM: The main idea in the book is what I call resourcefulness. Unless you understand something in several different ways, you are likely to get stuck. So the first thing in the book is that you have got to have different ways of describing things. I made up a word for it: "panalogy." When you represent something, you should represent it in several different ways, so that you can switch from one to another without thinking. The second thing is that you should have several ways to think. The trouble with AI is that each person says they're going to make a system based on statistical inference or genetic algorithms, or whatever, and each system is good for some problems but not for most others. The reason for the title The Emotion Machine is that we have these things called emotions, and people think of them as mysterious additions to rational thinking. My view is that an emotional state is a different way of thinking. When you're angry, you give up your long-range planning and you think more quickly. You are changing the set of resources you activate. A machine is going to need a hundred ways to think. And we happen to have a hundred names for emotions, but not for ways to think. So the book discusses about 20 different directions people can go in their thinking. But they need to have extra meta-knowledge about which way of thinking is appropriate in each situation. TR: Are you saying that computers should get angry? ..."
• And be sure to also listen to this interview: This Week on Philosophy Talk - Artificial Intelligence (May 20, 2007 radio broadcast; audio available online). With Ken Taylor and John Perry of Stanford University and guest, Marvin Minsky. KALW, 91.7 FM, San Francisco.

Emotional Design. Beauty and brains, pleasure and usability go hand-in-hand in good design. By Donald A. Norman. Ubiquity (Volume 4, Number 45; January 13-19, 2004). "Because emotion is so essential to survival, they will be equally essential for the artificial machines -- robots -- that are designed to work autonomously, intelligently, without supervision for months or even years. Just as animals and people need emotions for survival and learning, so too will machines -- not human emotions, but emotions relevant to machine life. That's the argument presented in the last two chapters of 'Emotional Design.'"

Emotionware. By Lynellen D.S. Perry (1996). ACM Crossroads Student Magazine. "The capability of displaying emotion seems to be a critical component of creating intelligent agents with whom humans can comfortably relate and communicate. The emotional aspect distinguishes a dead machine from an agent who is believable, alive, and trustworthy."

Does HAL Cry Digital Tears? Emotions and Computers. By Rosalind W. Picard. From HAL's Legacy: 2001's Computer as Dream and Reality. Edited by David G. Stork. (MIT Press, 1996). "Are emotions a desirable property for computers to have? It's hard to imagine someday walking into a computer store and saying, 'Give me the most emotional machine you've got.' After all, isn't possessing the highest form of rationality one of the hallmarks of computers? Aren't Mr. Spock and Data the unemotional patron saints of computer scientists? Imagine how a computer with emotion might work -- perhaps it would have to feel interested before it would listen to what you have to tell it. On the face of it, emotions in computers sound absurd. After all, didn't emotion cause HAL to malfunction? On the other hand, it would be tremendously worthwhile to have a computer that is congenial to interact with, flexible in its approach to doing what you want, makes snappy and intelligent decisions, and offers creative solutions to problems. It may surprise you to know that emotion plays a key role in all these qualities. In fact, emotion appears to be a necessary component of intelligent, friendly computers like HAL. The inability of today's computers to recognize, express, and have emotions severely limits their ability to act intelligently and interact naturally with us."

These machines 'really seem to care' - Software would let devices 'sympathize,' understand, nag if they must. By Vito Pilieci. The Ottawa Citizen (June 8, 2001). "I and A Research of Saint-Sauveur says it has developed a software technique -- Emotional Modelling for Intelligent Response -- that can synthesize data received through weather monitors or computer search engines and express 'feelings' that mimic a human's reaction to the information input. The technique, says company president Charles Guerin, has already produced applications to help pilots make decisions on whether to fly in poor weather, to effectively alert someone when a refrigeration system is malfunctioning, and to help online researchers locate photographs or texts that capture certain moods and emotions."

Letting your computer know how you feel. By Cliff Saran. ComputerWeekly (June 24, 2003). "Kate Hone, a lecturer in the department of information systems and computing at Brunel University, is the principal investigator in a project that aims to evaluate the potential for emotion-recognition technology to improve the quality of human-computer interaction. ... Affective computing can be defined as 'computing that relates to, arises from, or deliberately influences emotion'. A number of different types of research are encompassed within this term. For instance, some artificial intelligence researchers in the field of affective computing are interested in how emotion contributes to human and, by analogy, computer problem solving or decision making..."

Why robots will have emotions. by Aaron Sloman and Monica Croucher. In Proceedings 7th International Joint Conference on AI, pp. 197--202, 1981, Vancouver. "Abstract: Emotions involve complex processes produced by interactions between motives, beliefs, percepts, etc. E.g. real or imagined fulfilment or violation of a motive, or triggering of a 'motive-generator', can disturb processes produced by other motives. To understand emotions, therefore, we need to understand motives and the types of processes they can produce. This leads to a study of the global architecture of a mind. Some constraints on the evolution of minds are disussed. Types of motives and the processes they generate are sketched."

Marvin Minsky Wants Machines To Get Emotional. By Tom Steinert-Threlkeld, ZDNet/Interactive Week. (February 25, 2001). "Because the main point of the book [The Emotion Machine] is that it's trying to make theories of how thinking works. Our traditional idea is that there is something called 'thinking' and that it is contaminated, modulated or affected by emotions. What I am saying is that emotions aren't separate."

When Robots Weep: Emotional Memories and Decision-Making. By Juan D. Velásquez. 1998. In Proceedings of the Fifteenth National Conference on Artificial Intelligence, 70 - . Menlo Park, Calif.: AAAI Press. "We describe an agent architecture that integrates emotions, drives, and behaviors, and that focuses on modeling some of the aspects of emotions as fundamental components within the process of decision-making. We show how the mecha-nisms of primary emotions can be used as building blocks for the acquisition of emotional memories that serve as biasing mechanisms during the process of making decisions and selecting actions. The architecture has been implemented into an object-oriented framework that has been successfully used to develop and control several synthetic agents and which is currently being used as the control system for an emotional pet robot."

Affective Computing at the MIT Media Lab. "Our research is aimed at giving machines skills of emotional intelligence, including the ability to recognize, model, and understand human emotion, to appropriately communicate emotion, and to respond to it effectively. We are also interested in developing technologies to assist in the development of human emotional intelligence. ... Applications include the development of intelligent human-computer systems that learn from natural interaction, wearable computers for health and fitness, sensors for measuring and reducing frustration in new products, tools for human expression, and the development of new computational theories of affect and learning."

The Cognition and Affect Project at The University of Birmingham School of Computer Science. "We are investigating principles for designing or explaining architectures for 'whole' intelligent agents, combining many kinds of functionality, whether natural or artificial."

• Two toy 'emotional' agents moving around. A SimAgent demo movie from the School of Computer Science, The University of Birmingham. "Of course, this is just a shallow toy developed for tutorial purposes rather than anything that could be said to have human-like emotions -- except insofar as some (but not all) human emotions involve reacting to things that achieve or hinder goals or desires. ... These agents differ from many so-called emotion simulations in that these creatures have some self-knowledge so that they not only show their state (in facial expressions and in movements) but also describe them (which humans cannot always do!)."

Emotion Home Page - "a repository of information about emotion research. The goal of this site is to function as a web-space for the exploration of emotion research. It is intended as a tool for visitors interested in the scientific study of emotion and is limited to experimental and clinical psychology, neuroscience and computational perspectives." Maintained by Jean-Marc Fellous and Eva Hudlicka at Duke University. Be sure to check out:

• Artificial Intelligence / Cognitive Science
  • Framework
  • Computational models
  • Bibliography
• Places and People

Kismet: A Sociable Humanoid Robot. Humanoid Robotics Group, MIT Artificial Intelligence Laboratory. Well-written text complemented by delightful images, not to mention severalvideo clips, make this an excellent site for getting to know a robot, up-close and personal.

Symposium on Emotion, cognition, and affective computing. AISB'01 Convention, 21st - 24th March 2001. University of York, United Kingdom. "In recent years there has been much diverse work which explores the use of computing in ways which involve human emotion. This area is commonly referred to as affective computing. This includes work on the use of emotions in human-computer interaction, AI and agent architecures which are inspired by the mechanisms of emotion, the use of emotion in computer-mediated communication, the study of human emotion through computers and philosophical issues concerning, for example, the extent to which it is meaningful to talk about emotion in computational terms. Much work has been done in these areas in recent years, and we feel that this symposium will present an opportunity to bring together and consolidate these ideas, and raise questions about future directions for this area of study."

Vikia and the Social Robot Project. Carnegie Mellon University Robotics Institute, Human Computer Interaction Institute, and Entertainment Technology Center. "The goal of the Social Robot Project is to overcome the human-robot social barrier. Towards this end, we are in the process of developing a robot which bears a personality, and which can behave according to social conventions. The idea is that communication and interaction with robots should be easy and enjoyable, both for unfamiliar users and trained professionals. We want robots to behave more like people, so that people do not have to behave like robots when they interact with them."

Related AI Topics Pages

• Cognitive Science
• Interfaces
• Reasoning
• Robots
• Video Games

Other References Offline

Norman, Donald A. 2004. Emotional Design: Why we love (or hate) everyday things.' Basic Books. Reviewed by Charles Arthur: Machines have feelings too - A new book argues that computers should be given emotions. The Independent (November 5, 2003). "Professor [Donald] Norman's thesis is that emotion - that is, gut reaction - is an essential part of our reaction to anything we interact with. Don't dismiss emotion, he argues: it's a useful function that evolution has equipped us with so that we don't have to think about everything. ... But Professor Norman goes rather further than this. He doesn't just consider what makes us react to machines and objects that we use: he takes the thinking forward to pondering the question of whether machines - such as robots and computers - should have emotions. He thinks they should, as does Professor Rosalind Pickard, an artificial intelligence expert. She told him: 'I wasn't sure [machines] had to have emotions until I was writing a paper on how they would respond intelligently to our emotions without having their own. In the course of writing that paper, I realised it would be a heck of a lot easier if we just gave them emotions.'"

Oatley, Keith. Emotion. Entry in the MIT Encyclopedia of Cognitive Science. "Prompted by difficulties of Cognitive Modeling in capturing what is essential about the organization of human action, Simon [Simon, H. A. (1967). Motivational and emotional controls of cognition. Psychological Review 74:29-39.] argued that because resources are always finite, any computational system operating in any complex environment needs some system to manage Planning, capable of interrupting ongoing processes. The system for handling interruptions can be identified with the emotional system of human beings."

Picard, Rosalind. W. 1997. Affective Computing. MIT Press. "The latest scientific findings indicate that emotions play an essential role in decision making, perception, learning, and more--that is, they influence the very mechanisms of rational thinking. Not only too much, but too little emotion can impair decision making. According to Rosalind Picard, if we want computers to be genuinely intelligent and to interact naturally with us, we must give computers the ability to recognize, understand, even to have and express emotions."

Simon, H. A. 1967. Motivational and emotional controls of cognition. Psychological Review 74:29-39.