birthday cake
My earliest clear memories of events I experienced, which are not simply memories of stories told to me about my childhood, are from when I was 4 years old. I know, because those memories are clearly situated at and near the apartment in Minneapolis where we lived when I was 4, from which we moved about the time I turned 5. One of those memories, which would have occurred when I was about 4 years and 4 months, is the following. On a hot summer day, my grandmother told me that it was time for me to take an adventure by myself. We lived on a busy street with traffic lights, and I'm sure that my grandmother had already explained to me how to cross streets at lights as we took walks together. But this day, she told me, I would go by myself, a distance of about two blocks, crossing at least one busy street, to buy myself a popsicle and then walk back home.

She would sit on the stoop and watch to make sure I came back OK. I did. And then, after that, I could take walks like that myself, to get things my grandmother or others in the family needed, without having to be watched. I'm sure that one reason I remember this event so well is that it was very exciting to me, a big step toward growing up.

There are a number of significant things to note about this memory. First, this was seven decades ago, back when it wasn't unusual to see little kids walking along the sidewalk and crossing streets unaccompanied by an adult. There was no fear that someone would call the police or Child Protective Services. If Jack were 4, you might not want to trust him to make a good bargain on his sale of the cow (he might trade it for beans), but you could trust him to walk to the marketplace and find his way back. Second, this illustrates something that parents (or grandparents, as in my case) did in those days; they taught kids safety rules, so they could safely gain independence, rather than protecting them from independence.

But the point I want to elaborate on now has to do with motivational and cognitive changes that occur in children at around age 4, which make children both desirous of and capable of increased independence. It is significant that, back then, it would have been common to see 4-year-olds out on adventures by themselves, but not 3-year-olds. Three-year-olds might be out with their 5-year-old siblings, but rarely if ever alone.

The Age of Independence in Hunter-Gatherer Bands and Sudbury Schools

Some years ago, I delved into the lives of children in hunter-gatherer bands by surveying anthropologists and reading all I could find on the topic (see here and here). One thing I learned is that hunter-gatherers typically view children as "infants" up until about 4 years old, and as "children who have sense" (to use a phrase quoted by one anthropologist) beginning at about 4 years old. Children under age 4 are often still nursed by their mothers, and although they are free to engage in many adventures around the campsite and to accompany adults or older children on trips, they are not allowed to - and apparently have little desire to - venture out of sight and hearing of adult or older-child caregivers. Four-year-olds, in contrast, are generally free to run with the other kids, or even alone, away from caregivers. Millennia of experience have taught hunter-gatherers that by the age of about 4 (of course, it varies somewhat from child to child), children not only begin to seek independence from adults, but are capable of it.

Even more years ago, when I first became interested in the Sudbury Valley School, where children freely pursue their own interests all day (e.g. here and here), I was intrigued to learn that the youngest students the school would accept were 4 years old. At this school, all students, regardless of age, are free to roam anywhere on the school's 10-acre campus, which is not fenced off from its surrounds. Adults do not follow the students around. Students, regardless of age, are expected to take responsibility for their own safety. The campus includes a millpond with a dam and is bordered on one side by a road with traffic and on another side by a state forest where someone could get lost. It also has huge rocks and trees to climb and one of those old-fashioned, "dangerous" high slides in the playground.

The judgment of the school has always been that most 4-year-olds are capable of being responsible for their own safety in this environment, but most 3-year-olds are not. (I should add that the school requires a visiting week of all prospective students, regardless of age, in which they must prove their ability to be responsible; so not all 4-year-olds are accepted.) The policy has turned out to be wise. Over the school's 50-year history, no students have died or even been seriously injured. The policy has since been adopted by most of the schools throughout the world that are modeled after Sudbury Valley.

The Shift From Attachment to Independence

If you read the literature on child development and advice to parents - especially if you read the older literature, before "experts" began to see it as their job to frighten people - you will find a continuous refrain about how at age 4, children begin to need and seek greater independence from adults. Even today, some of that can be found on the Internet if you Google "children age 4." Here are some examples:

- "Children this age [age 4] go from 0 to 60 on the independence scale, so it's vital to talk to them about safety rules before they get any big ideas," says Daniel Coury, M.D., chief of developmental and behavioral pediatrics at Nationwide Children's Hospital, in Columbus, Ohio. "But you don't want to scare them off." (Here.)

- "Four-year-olds want to try new experiences. They also want to be more self-reliant and seek to expand the areas of their lives where they can be independent decision-makers." (Here.)

- What a four-year-old would say about his or her needs: "I need to explore, to try out, and to test limits." (Here.)

Research on attachment, going all the way back to the work of Bowlby (1958) and Ainsworth (1979), has revealed that children's attachment to caregivers begins to increase around age 6 to 8 months and declines at about age 4 years. From an evolutionary perspective, this makes perfect sense. Six to 8 months is when infants begin to move around on their own (initially by crawling), so a strong drive to be near a reliable caregiver is adaptive, so they don't stray off too far and get into danger. Around 4 years is when children begin to have common sense, so there is much reduced danger in their straying off. The primary function of attachment (I hate to be so cold about it) is to protect the child from danger during the period when he or she is mobile, but has not yet acquired much sense about what is dangerous and what isn't.

The Internalization of Language and Origin of Verbal Thought

What underlies the increased ability of children, at about age 4, to behave safely and independently? Part of the answer, of course, simply has to do with increased knowledge. If caregivers have done their job properly and allowed children to explore and behave in moderately risky ways in the caregivers' presence during the children's first four years, then, by about age 4, children have learned a lot about what is safe and what isn't. But something less gradual also occurs just before or around age 4: Children develop the capacity to use words not just to communicate with others, but also to communicate with themselves. In other words, they begin to think verbally, which means, essentially, that they can tell themselves what is safe or not and can recall verbal rules that they learned from others, and they can use those abilities to restrain or motivate their actions as they roam and explore on their own.

The person most noted for this theory that a major shift in thinking occurs around age 4 is the Russian developmental psychologist Lev Vyotsky (1934/1962). Vygotsky contended that what we usually describe as thinking is, largely, internalized speech. At first, according to Vygotsky, thinking occurs in a social context, as back-and-forth speech with others. An older person says something to the child. The child understands what was said and may or may not argue. If the statement is a rule of behavior, the child may abide by it immediately, but not sometime later, because the child doesn't think of it later. That's why very young children need to be watched. Over time, however, children learn that they can use language even when not in the presence of others, as a way of reminding themselves what they should or should not do. At first, they may use the words aloud, in a phase of talking to themselves: "Oh, Mommy said don't touch the hot stove." But with time they learn that they don't have to actually enunciate the words; they can just think them to themselves. There is sometimes a transitional period where you can see the child's lips move as he or she thinks. If you are a lip reader, you can literally read the child's mind.

According to Vygotsky, and verified by much research since his time (e.g., Alderson-Dat & Fernyhough, 2014; Manfra et al., 2014; Winsler et al., 1997), by about age 4, children have developed the capacity for verbal thought to such a degree that they can recall and follow rules that they learned previously without someone there to remind them, and can even think verbally about how to behave in new contexts. They can ask themselves such questions as, "Is it safe for me to do this?" or "What would happen if I did that?" and imagine the answer before they actually try this or that. This ability is the essence of common sense and caution.

The Emerging Understanding of Minds

Another well-documented cognitive shift that occurs at around age 4 concerns what researchers call "theory of mind" (e.g. Wellman, Cross, & Watson, 2001.). Theory of mind refers to the understanding that there is a difference between what a person may believe to be true and what is actually true. People can hold, and act upon, false beliefs. One person can believe one thing, and another can believe something else. This understanding is an important development in the child's ability to get along with peers. To have real friends and to truly collaborate, you must understand that the thoughts and perspectives of the friend are not necessarily the same as yours. Thus, to get along, it is necessary to somehow learn about the mind of your friend and take that into account in your play. It is no coincidence, I think, that this ability emerges around the same time that children are motivated and able to enjoy play with peers, without intervention by adults. Most 4-year-olds, unlike most 3-year-olds, can play happily with others their own age, because they can take into account the needs and knowledge of their playmates, which may be different from their own needs and knowledge.

I suspect (though I don't know of any research on it) that the development of theory of mind is intimately linked to the internalization of language. When children talk to themselves as a way of thinking, they almost can't help but begin to become aware of the fact that they have a mind, and that their mind can change over time: "I think there is a toy in this box. Now I'm opening the box. Oops, there's no toy. I was wrong." Once they realize that they have a mind, which can change over time in its knowledge and beliefs, it is a relatively small step to realize that the same is true for other people. The mind is what people say to themselves.

It is also no coincidence, then, that age 4 is when children typically begin to enjoy tricks and riddles and guessing games. To enjoy these things, you have to understand that the mind can be fooled. Understanding that also helps you to behave safely when out adventuring. You know that your current belief, or what a playmate just told you, could be wrong, so you test it out before you act on it.

Conclusion

Throughout human history, until very recently, people understood that the capacity for common sense, restraint, and self-controlled safety grows rather rapidly at around age 4. Age 4 was understood as the approximate age at which children enter the culture of childhood, where they begin to learn at least as much, if not more, from play with peers as from adults. People didn't need research studies to prove it to them; it was obvious. Children today, sadly, exist in a world in which adults have become convinced that children are not competent at age 4, and many believe that they are not competent even at age 8 or 12. Many 12-year-olds today are not permitted the independence that 4-year-olds were permitted until just a few decades ago.


We also, sadly, live at a time when many people hold the really weird belief that it is more important to train little children in so-called "academic skills" than to teach them basic rules of safety - rules that they can understand and that could give them the freedom they need to learn lessons that are far more important than the scraps of academia we force onto them.