Homo Prospectus
Introduction
Peter Railton
THE FOUNDER OF MODERN PSYCHOLOGY, WILLIAM JAMES,
wrote in his magnum opus, Principles of Psychology, "My thinking is first, and last, and always for my doing" (James, 1890, p. 960). Certainly, evolutionary considerations argue in favor of this broad idea. Nature is not the College Board—one does not get points simply for coming up with the right answer, rather, getting the right answer matters because it affects how one behaves. Gathering food, seeking shelter, finding mates and allies, caring for the young, and all the while taking risks for uncertain gains—these are the activities that alter the fate of one's offspring and relatives.
But James might have added, "... and all of my doing extends forward in time, not backward." This seemingly obvious qualification has profound implications for the architecture of mind, whether human or animal, natural or artificial. Imagine an everyday bit of behavior, a deer running across the forest floor, a bird approaching its nest in a tree swaying in the wind, a human hurrying down the hallways of an unfamiliar office building, late for an appointment. Each of these behaviors can be done more effectively and efficiently if the individual anticipates what will come next: The deer moves quickly through the scattered branches and fallen trees by looking a few bounds ahead to anticipate where a clear path lies; the bird avoids missing the edge of the nest by anticipating its movement as the branch sways; and the human avoids wrong turns, doubling back, or having to slam on the brakes by glancing at the office numbers and anticipating how they will change in the hallway ahead. The behavior is more effective because it is likely to be more successful than proceeding without anticipation, and the behavior is more efficient because the same task is typically accomplished in less time, with less effort, and with fewer injuries.
All animals live on a limited budget of energy and time, and so must ensure that they do not expend their last energy before they have found a way to replenish. This constraint is severe. A scrub jay who, over the course of a day, caches too much food and eats too little, will arrive at sunset with insufficient energy stored in its body to escape perishing during the long winter night; another who today caches too little and eats too much will last the night, but perhaps not tomorrow night, if tomorrow turns out to be a poor day for finding food. Modern-day humans are descended from ancestors who faced such limited time and energy budgets, and even today we have not escaped these limitations. In some human populations, finding a way to secure enough nutrition for oneself and one's family is a recurrent problem, while in others, time is the limiting factor, and using anticipation to invest time effectively and efficiently is vital to how well they manage in life. Food deprivation can give a creature hunger and a physiological urge to eat, but anticipation can intelligently regulate motivation to enable a creature to avoid hunger in the first place.
Competition, too, favors anticipation. Predators that are better than their prey at anticipating the other's movement will have a critical advantage. The deadliest predator on the planet is not the strongest or swiftest, but the one with the longest time horizon of anticipation, Homo sapiens. For any reasonably healthy animal, predator or prey, adding some capacity to anticipate can be worth more than an increment in strength, speed, or dexterity. Indeed, adding such capacity can itself yield gains in speed, strength, or dexterity, and without adding an ounce of new muscle tissue. As the running deer, returning bird, and hurried human suggest, muscles and joints can be used more effectively and efficiently if guided by an anticipation of what comes next.
And coordination and cooperation can equally benefit from anticipation. How would we coordinate and cooperate if we could not form reliable expectations of what others would do in a range of situations? Or have reliable expectations of what we ourselves will be able to do or be sufficiently motivated to do? Anticipation can even make you smarter in ways that may matter most. Just think of the last time you made what you'd describe as a stupid remark, purchase, bet, promise, or attempted repair and thought, "if only I'd thought ahead just a little bit more." For social animals, intelligent interaction with conspecifics—mates, offspring, relatives, and potential allies or rivals—is just as critical for reproductive success as intelligent interaction with the physical world.
Scarcity and competition, and coordination and cooperation, are two sides of the same evolutionary coin. Coordination and cooperation, whether across generations within a family or across families within a generation, are key ways intelligent animals contend with the threats posed by scarcity and competition. Taken together, they make the case that natural selection strongly favored development of a capacity to anticipate and harnessed this capacity to the regulation of behavior, thus, tying "my thinking ahead" to "my doing," as our amendment to James would put it.
Why, then, aren't all creatures equipped with the long time horizon of human anticipation? Anticipating better-than-chance what will happen next becomes greatly more complicated as one looks further into the future. So do the mental structures needed to make use of such advance information in action, such as imagination, planning, and self-control. The basic mental structures that underlie anticipation are remarkably simple, and so they are ubiquitous in the brains of intelligent animals. But their elaboration into a brain that can think a year or more ahead with some chance of successful prediction, and some chance of actually using this prediction to regulate its life in the here and now, turns out to require a very expensive brain and a very long apprenticeship in life, such as we find in humans. There are, then, trade-offs in developing anticipation, as there are for any capacity worth having. And so there are many ways of making this trade-off to solve problems of scarcity and competition effectively within a given environmental niche without going the whole route to Homo sapiens. Hence, the world is full of intelligent anticipators of all shapes, sizes, and time horizons.
We are emphasizing anticipation, but don't intelligent anticipators need past experience to anticipate well? So why say that the mind is forward-looking if it must look backward for its evidence? Or why say that skill has an architecture of anticipation if it must be founded upon a history of practice? Of course, learning is required if one is to manage the task of anticipating well; just compare the physical, mental, and social dexterity of typical human adults with that of typical human 2-year-olds. And it is true that at a given moment, all of one's learning took place in the past. Missing from this description, however, is a characterization of how we learn.
Anticipation, it turns out, is at the heart of effective learning, for it is through the formation of expectations that an animal is able to detect error and metabolize experience selectively into useable information. But what about memory? Surely its essence is not about the anticipation of future experience, but about the preservation of past experience. A growing body of evidence, however, suggests that this is not its essence: Memory "retouches" our recollections in a continuing, dynamic interaction with ongoing thought and experience (Nader, 2003). That seems like a fault, but this book is about why that is the right design for memory to have.
In this book we will use the term prospection as a label for the mental process of projecting and evaluating future possibilities and then using these projections for the guidance of thought and action (Buckner & Carroll, 2007; Gilbert & Wilson, 2007). Like an old-time prospector searching for gold, the mind's processes of prospection map out not just the physical landscape lying ahead, but an array of possible paths through that landscape. Like an old-time prospector, too, the mind must select among these paths in the face of uncertainty and partial information. So an estimation must be made of the promise of the different paths relative to sought-after goals, given the likely risks and costs. Because neither future possibilities nor their estimated value can be seen, heard, felt, or smelled, these are not features of the world that are presented to the mind by perception, past or present. The mind must add them. The mind must, therefore, have a way of representing these possibilities and anticipated values, making these parts of the mental landscape as real and forceful as the features of the physical landscape presented by the senses. A prospecting mind must do the "seeing" and "feeling" that simulate what a future will be like, and thereby place future possibilities on all fours with what is actually seen and felt at present. That is the job of prospection.
And that is why we will be arguing that Homo sapiens describes an outcome of human nature, not its origin. For sapiens means wise, and we are not born wise. Neither do we grow into wisdom the way a seed grows into a sprout and then a plant. We must learn to be wise. And learning is a chancy matter that depends on how well the architecture of expectation operates to extract information from experience. So we are at our beginning Homo prospectus, who might or might not make it all the way to sapience. But even "Homo prospectus" still omits a critical part of the process, for no individual Homo could learn to be truly wise entirely on his or her own. Much of what we learn over the course of our lives arises not from solo experience, but from observation of, and interaction with, others. Other species, too, are capable of social learning, although it appears to be confined in ways that might have something to do with some limitations of their ability to project themselves mentally into a standpoint that is not their own. Hence, the true origin of Homo sapiens is the distinctive combination of an unprecedented capacity for anticipatory guidance and an unprecedented capacity to live and learn with others—capacities definitive of our ultimate subject matter in this book, Homo prospectus socialis; more simply, Homo prospectus.
It's time we met him—or her—in person.
