This book tries to explain how minds work. How can intelligence emerge from nonintelligence? To answer that, we'll show that you can build a mind from many little parts, each mindless by itself.
I'll call "Society of Mind" this scheme in which each mind is made of many smaller processes. These we'll call agents. Each mental agent by itself can only do some simple thing that needs no mind or thought at all. Yet when we join these agents in societies-in certain very special ways-this leads to true intelligence. There's nothing very technical in this book. It, too, is a society-of many small ideas. Each by itself is only common sense, yet when we join enough of them we can explain the strangest mysteries of mind. One trouble is that these ideas have lots of cross-connections. My explanations rarely go in neat, straight lines from start to end. I wish I could have lined them up so that you could climb straight to the top, by mental stair-steps, one by one. lnstead they're tied in tangled webs. Perhaps the fault is actually mine, for failing to find a tidy base of neatly ordered principles. But I'm inclined to lay the blame upon the nature of the mind: much of its power seems to stem from just the messy ways its agents cross-connect. If so, that complication can't be helped; it's only what we must expect from evolution's countless tricks. What can we do when things are hard to describe? We start by sketching out the roughest shapes to serve as scaffolds for the rest; it doesn't matter very much if some of those forms turn out partially wrong. Next, draw details to give these skeletons more lifelike flesh. Last, in the final filling-in, discard whichever first ideas no longer fit. That's what we do in real life, with puzzles that seem very hard. [t's much the same for shattered pots as for the cogs of great machines. Until you've seen some of the rest, you can't make sense of any part. I.I THE AGENTS OF THE MIND Good theories of the mind must span at least three different scales of time: slow, for the billion years in which our brains have evolved; fast, for the fleeting weeks and months of infancy and childhood; and in between, the centuries of growth of our ideas through history. To explain the mind, we have to show how minds are built from mindless stuff, from parts that are much smaller and simpler than anything we'd consider smart. Unless we can explain the mind in terms of things that have no thoughts or feelings of their own, we'll only have gone around in a circle. But what could those simpler particles be-the "agents" that compose our minds? This is the subject of our book, and knowing this, let's see our task. There are many questions to answer.
Function: How do agents work?
Embodiment: What are they made of?
Interaction: How do they communicate?
Origins: Where do the first agents come from?
Heredity: Are we all born with the same agents?
Learning: How do we make new agents and change old ones? Character: What are the most important kinds of agents? Authority: What happens when agents disagree?
Intention: How could such networks want or wish?
Competence: How can groups of agents do what separate agents cannot do?
Selfiness: What gives them unity or personality?
Meaning: How could they understand anything?
Sensibility: How could they have feelings and emotions? Awareness: How could they be conscious or self-aware?
How could a theory of the mind explain so many things, when every separate question seems too hard to answer by itself? These questions all seem difficult, indeed, when we sever each one's connections to the other ones. But once we see the mind as a society of agents, each answer will illuminate the rest.
There is no singularly real world of thought; each mind evolves its own internal universe. The worlds of thought that we appear to like the best are those where goals and actions seem to mesh in regions large enough to spend our lives in-and thus become a Buddhist, or Republican, oi poet, oi topologist. Some mental starting points grow into gteat, coherent continents. In certain parts of mathematics, science, and philosoPhy, a relatively few but clear ideas may lead into an endless realm of complex yet consistent new structures. Yet even in mathematics, a handful of seemingly innocent rules can lead to complications far beyond our grasp. Thus we feel we understand perfectly the rules of addition and multiplication-yet when iye mix them together, we encounter problems about prime numbers that have remained unsolved for centuries. Minds also make up pleasant worlds of practical affairs-which work because we make them work, by putting things in order there. In the physical realm, we keep our books and clothes in self-made shelves and cabinets-thus building artificial boundaries to keep our things from interacting very much. Similarly, in mental realms, we make up countless artificial schemes to force things to seem orderly, by specifying legal codes, grammar rules and traffic laws. When growing up in such a world, it all seems right and natural-and only scholars and historians iecall the mass of precedents and failed experiments it took to make it work so well. These "natural" worlds are actually more complex than the technical worlds of philosophy. They're far too vast to comprehend-except where we impose on them the rules we make. There is also a different and more sinister way to make the world seem orderly, in which the mind has merely found a way to simplify itself. This is what we must suspect whenever some idea seems to explain too much. Perhaps no problem was actually solved at all; instead, ihe mind has merely found some secondary pathway in the brain, through which one can mechanically dislodge each doubt and difference from its rightful place! This may be what happens in some of those experiences that leave a person with a sense of revelation-in a state in which no doubts remain, or with a vision of astounding clarity-yet unable to recount any details. Some accident of mental stress has temporarily suppressed the capacity to question, doubt, or probe. One remembers that no questions went unanswered but forgets that none were asked! One can acquire certainty only by amputating inquiry. When victims of these incidents become compelled to recapture them, their lives and person* alities are sometimes permanently changed. Then others, seeing the radiance in their eyes and hearing of the glory to be found, are drawn to follow them. But to offer hospitality to paradox is like leaning toward a precipice. You can find out what it is like by falling in, but you may not be able to fall out again. Once contradiction finds a home, few minds can spurn the sense destroying force of slogans such as "all is one."