Short works

Books : reviews

Marvin L. Minsky.
Computation: Finite and Infinite Machines.
Prentice-Hall. 1967

This absorbing book is unique in the literature of the field. It provides the professionals—computer programmers, mathematicians, electrical engineers—with an introduction to the central concepts underlying the evolving “Theory of Machines,” the theoretical background on which the study of what can and what cannot be done with computers is based. It offers a provocative and easily understood insight into the fundamental theoretical concepts of computation, and describes some mathematical ideas involved in the analyses of discrete systems.

Dependent on only a basic knowledge of algebra for comprehension this valuable study develops its own mathematics where necessary and covers the vast range of its subject, from basic principles to current research problems.

The prime goal of this study is to introduce the concept of effective procedure—a vital intellectual tool employed in the development of theories about complex systems and necessary to understanding of the idea of proof itself. Another theme of this book is the multi-faceted concept of the universal computer—a theoretical and practical device through which a great complexity of behaviour can arise from the interactions of simple devices, actions, descriptions, or concepts. Following an introductory section, the work is divided into three major sections—

• finite-state machines
• infinite machines
• symbol-manipulation systems and computability

Through the work, sample problems, and their solutions, are offered in illustration, and the text is augmented by a glossary of terms and a table of special symbols. In all, this book comprises an essential tool in the hands of anyone whose professional range encompasses computers and their use.

Marvin L. Minsky.
The Society of Mind.
Simon & Schuster. 1985

rating : 1.5 : unmissable
review : 22 August 2004

This seminal work on how a brain might make a mind is just as relevant today as when it was first published twenty years ago. Minsky explains how lots of very simple agents might come together as agencies and result in intelligent behaviour. The structure of the book reflects this architecture -- each individual page is a short "chapter" explaining some nugget of the theory, and the cumulative effect is the totality of the argument. Some of the ideas are quite specific, and may be wrong in detail (for example, I remain unconvinced by the sections on humour), but the overall argument remains sound.

(One thing that has changed dramatically since the book was first published: the fact that I've finally managed to get hold of a copy of this long out-of-print work is a testament to Amazon's second-hand sales webpages.)

Marvin L. Minsky, Seymour A. Papert.
Perceptrons: extended edn.
MIT press. 1988

Marvin L. Minsky.
The Emotion Machine: commonsense thinking, artificial intelligence, and the future of the human mind.
Simon & Schuster. 2006

rating : 2.5 : great stuff
review : 19 March 2007

Our minds are working all the time, but we rarely stop to think about how they work. The human mind has many different ways to think, says Marvin Minsky, the leading figure in artificial intelligence and computer science. We use these different ways of thinking in different circumstances, and some of them we don’t even associate with thinking. For example, emotions, intuitions, and feelings are just other forms of thinking, according to Minsky. In his groundbreaking new work, The Emotion Machine, Minsky shows why we should expand our ideas about thinking and how thinking itself might change in the future.

The Emotion Machine explains how our minds work, how they progress from simple kinds of thought to more complex forms that enable us to reflect on ourselves—what most people refer to as consciousness, or self-awareness. Unlike other broad theories of the mind, this book proceeds in a step-by-step fashion that draws on detailed and specific examples. It shows that thinking—even higher-level thinking—can be broken down into a series of specific actions. From emotional states to goals and attachments and on to consciousness and awareness of self, we can understand the process of thinking in all its intricacy. And once we understand thinking, we can build machines—artificial intelligences—that can assist with our thinking, machines that can follow the same thinking patterns that we follow and that can think as we do. These humanlike thinking machines would also be emotion machines—just as we are.

This is a brilliant book that challenges many ideas about thinking and the mind. It is as insightful and provocative as it is original, the fruit of a lifetime spent thinking about thinking.

This is a direct sequel to The Society of Mind, with some more details and explanations worked out, and the same style of diagrams. This time we get a discursive wander around possible structures of various cognitive processes, with various interjections from a range of critics.

Despite the title, there is actually very little on emotions as such. Minsky has an interesting take on them: he regards them as being a consequence of thinking, not as a causal factor in the process:

pp226. [Patient Elliot’s inability to decide, and emotionlessness] led Damasio to suggest that "reduced emotion and feeling might play a role in Elliot’s decision-making failures." However, I’m inclined to turn that around to suggest that it was Elliot’s new inability to make such decisions that reduced his range of emotions and feelings.

pp233-4. The expressions of rage ... could have served in primordial times to help to repel or intimidate the person or creature that one is angry with; indeed, any external expression of one’s mental state can affect how someone else will think. This suggests an idea about what we mean when we use our most common emotion-words; they refer to classes of mental conditions that produce external signs that make our behaviors more predictable to the persons with whom we are dealing. Thus, for our ancestors, those bodily signs served as useful ways to communicate such so-called "primary" emotions as Anger, Fear, Sadness, Disgust, Surprise, Curiosity, and Joy.
The body and face could also serve as a simple sort of memory ... your external expressions of anger may serve not only to frighten your enemies, but to also ensure that you will stay frightened for long enough to carry out some actions that might save your life.

If emotions are to be thought of as a consequence of cognition, I wonder how this fits with animal emotions? Minsky says only a little about evolutionary development, but his architecture does admit increasing levels and layers of sophistication in the processing (which is one of the regions where it is more developed than in The Society of Mind). Maybe Minsky would say that animals have much simpler cognitive systems, but that their emotions are nevertheless consequences of these simpler systems?

Despite not doing exactly what it says on the tin, however, this is a fascinating read. There seems to be more structure in the underlying model this time around, not just a pandemonium of agents competing to be heard over the din. Some questions are still begged: how do certain of the Recognisers manage to do their jobs? But it certainly feels like a not implausible model of what’s going on inside our heads.