The opening of SF State’s first hands-on ethnomathematics exhibit explores various mathematical principles introduced by different cultures throughout history and challenges participants to get involved.

Sponsored by the anthropology department and Treganza Anthropology Museum, the exhibit runs through April 28 in the department of anthropology’s Hohenthal Gallery (Science Building room 388.) Activities include recreating the elaborate sona sand drawings of the Chokwe people of northeast Angola, examining the geometric body paintings of the Mebengokre people of central Brazil, or just contemplating a game of mancala.

Mariana Ferreira, assistant professor of anthropology and exhibit co-organizer, explained the term and some of the principles behind it, while standing in front of the several different exhibit stations.

“Ethnomathematics involves much more than the just mathematics of indigenous people,” Ferreira said. “It’s actually an educational program to advance access of mathematical knowledge to people of color, and also acknowledge the contributions of people of color and indigenous people to mathematics.”

Andrea Fitzpatrick, a 26-year-old anthropology and creative writing double major, co-organized the event and was knowledgeable about the different styles of abacuses featured at one station.

An early counting device, the first abacus called the suan-pan, appeared in China around 1200 A.D., and has been modified only slightly in the past 800 years.

“The suan-pan is the original, it was the first rod abacus,” Fitzpatrick said. “The Japanese modified it a couple of times and in the 1920s it got the form it has now.”

The modern Japanese abacus – or soroban - has one bead in the top section and four on the bottom, while its predecessor has two beads on top and five on the bottom. The modern design allows for faster calculations during large equations, Fitzpatrick said.

Ferreira reminds us that math is a human creation, yet she said it becomes so engrained into the cultural makeup that certain principles may be taken for granted. However, differences in cultural values can drastically impact the way we view mathematics, and the world in general.

“The entire cosmology of every society is organized in a certain way, and that is where math actually begins,” she said.

Cultures that utilize a gift exchange economy, in which goods and services are distributed on the idea of gift giving, usually have different concepts of mathematics than those who live in a capitalist system.

“When you give, you don’t use a minus necessarily in your calculation,” Ferreira said. “Rather you use a plus.”

She explained that in a gift exchange economy a traditional math problem such as ‘you catch 10 fish and give three to your brother, how many do you have?’ Is not 10 minus three equals seven, but in fact can be viewed as seven plus three or even seven plus six, since the nature of the relationship is such that your brother will pay you back twice as much.

“It’s a completely different way of thinking that reflects the kind of logic and mathematical reasoning that shows us the close association between mathematics and capitalism, in which both help support the other,” Ferreira said. “Therefore when we think of mathematics we take for granted such concepts as giving implying a minus.”

In the Far East, complex Euclidian geometry equations are sometimes used as religious offerings.

“The Japanese have a tradition where mathematicians of all ages and genders come together to learn and solve problems,” said Miko Yamamoto, Treganza Anthropology Museum director and exhibit co-organizer. “Once the problem is solved, they put it on a wooden plaque and offer it to a shrine or temple. It’s a mixture of religion and science.”

Ferreira said she is considering weekly events – possibly Wednesdays at noon – so that speakers can come and meet with students who are interested in the field.

“One of the major goals of ethnomathematics as an educational program,” Ferreira said, “is to make the learning and teaching of mathematics more accessible to every student, parent, administrator, and the public in general.”