Amazonian children who never went to school understand the properties of points, lines and angles, proving the basic principles of geometry emerge regardless of education, a study said.
Eight children, ages 7 to 13, and 22 adults from the Mundurucu tribe in the Amazon, could identify the number of lines that can be drawn through two points, correctly complete unfinished triangles and estimate angles, according to a paper in the Proceedings of the National Academy of Sciences.
The 18th-century philosopher Immanuel Kant argued that humans have an intuitive understanding of geometry, which enables mathematicians to derive new, useful results. Abstract geometry may be innate, or it may be learned naturally through day-to-day interaction with the world, the authors wrote.
The test results “suggest Euclidean geometry, inasmuch as it concerns basic objects such as points and line on a plane, is a cross-cultural universal that results from the inherent properties of the human mind as it develops in its natural environment,” wrote the authors, who included Elizabeth Spelke, a specialist in developmental studies at Harvard University in Cambridge, Massachusetts.
The researchers also tested adults from the U.S., as well as French children 7 to 13 years old and American children from 5 to 7. The control groups showed the same performance profile as the Amazonians, except for the American children, who were younger, the researchers said.
The researchers asked the children and adults questions about lines, planes, angles, triangles and spheres. They were given sketches of lines and asked questions such as “Can a line be drawn through two points?” and “Can two such lines be drawn?”
All groups performed better at planar than spherical geometry, the study said.