Published here with permission from The MOORE REPORT INTERNATIONAL - November/December 2002
The Moore Foundation,
Box 1, Camas,
Adapted from Home Grown Kids by Raymond and Dorothy Moore
We have frequently referred to a child's ability to reason.
This development is closely related to the physical maturation of the senses and also the structure
and function of the brain.
Through the years of close observation and experiments with young children, the influential Swiss
psychologist, the late Jean Piaget, 1,2,3,4 came up with some very interesting and
significant findings about how children think.
These conclusions have been checked out by many other researchers and have been found to be valid.
He determined that the ability to understand a certain physical law is a sign of maturity in
This is the well-known law that mass is constant -- always the same -- regardless of its
arrangement or changes in shape.
He relates this understanding to the law of conservation of energy.
It is evidently not something that can be learned until a child is mature enough.
It has been found to bear close relation to readiness in beginning school tasks.
The age range for understanding this law is from about seven or eight to eleven or twelve.
The experiments to assess such reasoning ability take many forms.
For example, you can try this experiment on any four-year-old.
Show him two short, stout glasses of water the same shape and size and filled to the same levels.
Ask him if there is the same amount of water in both.
Of course, he will say "yes."
Then, while he is watching, pour the water from one glass into a taller, thinner glass.
Now ask him if there is still the same amount of water in both.
Often five-or six-year olds will answer that there is more in the tall container (because they
see that it is higher.)
A seven or eight-year-old will generally tell you that the amount is the same regardless of the
Recently an interesting couple joined us at dinner with their five-year-old boy and
Both children were thought "exceptional" by their parents, and indeed they were very bright.
We tried the glass and water experiment on the little boy while his older sister watched.
He responded as expected, saying there was more water in the taller glass.
We then asked his sister, knowing that she was not only older, but also a girl, and had had
more time to think it through.
But she gave the same answer.
Later we tried a similar Piagetian experiment taking two equal piles of ten pennies (or you
can use candies, or beans or other convenient item.)
We asked them to count out each pile and verify that each had ten.
We then spread one pile out into a line about eight inches long and left the other as it was.
When we asked the five-year-old if the two groups still had the same number of pennies, he said,
"No, there are more in the stretched-out line than in the pile."
This time his six-year-old sister hesitated.
She was not sure, and was therefore revealing some growth in such concepts, although a seven or
eight-year-old would normally realize the groups of pennies still contained the same number.
The parents looked on, astonished.
We decided to try just one more, this time a story which tests a child's understanding of
motive or reason, with implications for moral values.
We told them about little four-year-old Jimmy and his big sister, Sue.
Jimmy was angry when his mother would not give him dessert until he finished his vegetables, so
he smashed his glass on the floor.
Sue felt very badly for her mother and bent over to pick up the pieces, but in doing so, she
knocked off four glasses!
Who was the naughtiest, Jimmy or Sue?
The four-year-old unhesitatingly answered, "Sue." "Why?" "Because she broke the most."
To the parents' surprise, his sister agreed--showing typical inconsistency of a young child at
this transitional stage of development.
But some six and most seven- or eight-year-olds would normally recognize that the intention of
Sue was good and therefore she wasn't naughty at all.
These are simple illustrations of the reasoning ability of young children.
They serve to explain why, until now, many of your parental explanations of "why" have not seemed
to satisfy them.
This does not mean that you shouldn't tell a five-year-old why he should not, for example,
go into the street or climb up on the neighbor's garage roof.
We need to try to help children understand cause-and-effect relationships--the causes and likely
We would give them experiences that will develop their reasoning powers.
But we do need to recognize their limitations and not expect them to think like adults.
Few parents appear really to understand this need.
Occasionally our children's thought processes will astound us, and their clever ideas will make
us feel they are not very consistent in their reasoning, and that serious damage can be done to
children by urging them into tasks or situations or institutions requiring mental tools that
are simply not yet strong enough or sharp enough to do the job.
1 Piaget, J. "Development and Learning."
Journal of Research in Science Teaching 2(1964):176-86
2 _____________. "The Genetic Approach to the Psychology of Thought."
Journal of Educational Psychology 52(1961):275-81
3 _____________. The Origin of Intelligence in Children (trans. M. Cook).
New York: International Universities Press, 1952.
4 _____________. Science of Education and the Psychology of the Child.
New York: Viking Press, 1970.