We are Homo sapiens, the wise animal, who makes sense of the world, and so we have exploratory play, which combines playfulness with curiosity to help us understand our surroundings. Newborn babies, even on their first day out of the womb, look at patterns that are brand new to them in preference to patterns that they have already seen earlier in the day. Within a few weeks, babies start putting things within their reach into their mouths. Like puppies, they examine things orally, by mouthing them. By about 5 or 6 months of age, they transition to the uniquely human way of examining objects, with hands and eyes together. Put a novel object in reach of a 6-month-old and she will pick it up, hold it before her eyes, look at it, squeeze it, rub it, turn it over, pass it from hand to hand, shake it, pound with it, and act on it in various other ways that seem well designed to learn about its properties.
We come into the world as little scientists, pre-programmed to try to understand everything around us. Nobody has to tell us to explore and learn about our environment; we do it naturally, all our lives, in increasingly sophisticated ways, unless someone turns it into work by trying to make us do it.
Constructive play
We are the animal that survives by building things--including shelters, tools, devices to help us communicate, and devices to help us move from place to place--and so we have constructive play, which teaches us to build. In constructive play a child strives to produce some object that he or she has in mind. A child making a sandcastle, or creating a spaceship from blocks, or drawing a giraffe, is engaged in constructive play.
In many cases the objects built in constructive play are miniature or pretend versions of "real" objects that adults in the culture build and use. Hunter-gatherer children make small versions of huts, bows and arrows, blowguns, nets, knives, slingshots, musical instruments, digging sticks, rafts, rope ladders, mortars and pestles, and baskets in their play. Through such play they become good at building, and by the time they are adults they are making well-crafted, useful versions of the real things.
Constructive play can be with words and sounds as well as substances, and people everywhere, adults and children alike, produce stories, poems and melodies in their play. Among the countless kinds of constructions playfully made by children in our culture today are computer programs, written stories, and secret codes with invented symbol systems. Constructive play can be intellectual as well as manual.
Pretend and sociodramatic play
We are the imaginative animal, able to think of things that are not immediately present, and so we have fantasy play, or pretend play, which builds our capacity for imagination. In this type of play children establish certain propositions about the nature of their pretend world and then play out those propositions logically. In doing so they are exercising the same capacities that allow us, as adults, to think about things that are not immediately present, which is what we all do when we plan for the future and what scientists do when they develop theories to explain or predict events in the real world.
We are an intensely social species, requiring cooperation with others in order to survive, and so we have many forms of social play, which teach us to cooperate and to restrain our impulses in ways that make us socially acceptable. The social form of pretend play--in which children engage in elaborate joint pretend ventures and enact roles and scenes that they make up together--is called sociodramatic play. In such play, children are doing much more than just exercising their imagination. As they enact roles, they are exercising their ability to behave in accordance with shared conceptions of what is or is not appropriate. If you are the mommy, or the daddy, or the pet dog in a game of house, then you must behave in accordance with the players' shared understanding of how mommies, or daddies, or pet dogs behave. You cannot behave impulsively; you must think about what you are doing to be sure it will be acceptable. I will have more to say in a later essay about play as exercise in self-control. The learning of self-control is perhaps the most important general function of all sorts of human play.
Children in sociodramatic play are also practicing the art of negotiation. As they decide who will play what roles, who will get to use which props, and just what scenes they will enact and how, the players must all come to agreement. Indeed, a basic rule of all social play is that everyone must agree. Anyone left unhappy by a decision will quit, and if everyone quits there will be no game. Since the motive to play is strong, the motive to keep the other players happy is strong. That is true of all social play, but it is especially apparent in the negotiations that are observed in sociodramatic play. Keeping our companions happy, so they stay with us and continue to support us through life, is surely one of the most valuable of human survival skills, and children continuously practice that skill in social play.
Games with explicit rules
We are the rule-abiding animal, able to keep contracts and follow explicit, socially agreed-upon rules, and so we play formal games, which teach us to follow explicit rules.
All play to some degree involves rules. Rules in the minds of the players give structure to any form of play. In play fighting, for example, a basic rule is that you don't really hurt the other person--you don't kick, bite, or scratch, and if you are the larger and stronger of the two you don't use your full force. In constructive play a basic rule is that you must attempt to depict some object that you have visualized in your mind; you don't just scribble or pile blocks randomly. In sociodramatic play a general rule is that you must act in accordance with shared understanding of how the person or animal you are pretending to be would act. The rules in all of these forms of play are mostly implicit; they are understood but unstated. In formal games the rules are explicit, meaning that they are clearly stated, in categorical terms, in a way that makes it possible for observers to agree on whether or not the rules have been followed. All competitive games have such rules, as they are necessary to make the competition fair, but many non-competitive games do too. Dances and cooperative games like jump rope (of the variety where the goal is to keep the rope spinning and the jumper jumping as long as possible) are examples of cooperative games with formal rules.
Human beings everywhere must follow explicit as well as implicit rules to function socially. For example, a cooperative hunt may involve explicit rules concerning what each member of the hunting party must do and when. People also need to abide by rules or laws designed to keep peace within the community, and they need to follow through on social agreements (oral or written contracts) made between themselves and others. These crucial social skills are exercised in formal games.
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When children are free to play, have sufficient time to play, and have playmates of a range of ages with whom to play, they play in all of these ways. In doing so, they learn all of the basic skills that are required of human beings everywhere--physical skills, linguistic skills, intellectual skills, social skills, self-control, and law-abiding skills. We cannot teach any of these skills to children. All we can do is provide the conditions in which they can teach themselves, using the joyful, playful means designed by evolution. Our job is to make sure that children have lots of time and and opportunity to play. They'll take care of the rest.
