in collective behavior, including the acceptance of the comforts of sedentary
In Chapter 4, “Map-Making in São Paulo, Southern Brazil,” mathematics
educators show how map-making activities can lead to a critical awareness of the
social diversity and historical situation of Indigenous Peoples in Brazil. It is clear
that to construct and analyze information about the situation of Indigenous Peoples
and their lands in Brazil requires knowledge of mathematics. The argument here,
however, is that developing sensibility about sociocultural diversity raises awareness
and leads to action toward the protection of lands and resources, and thus the
liberation of Indigenous Peoples.
Part III: People and Numbers in Xavante Land, Central Brazil
Chapter 5, “The 2 of Us Together: Xavante Mathematics in Central Brazil Today,”
is a philosophical inquiry into the foundations of Xavante mathematical thought.
I discuss details of the Xavante dialectical worldview and the challenge it poses to
Xavante community members inside and outside of classroom situations today. The
solution to mathematical problems remain structured by the reciprocal principle of
gift-giving, and by the notion that for the Xavante people, a totality is always the
sum of two fundamental parts. The people's decision to adopt a decimal number
system for monetary transactions, in addition to their traditional numerical system
of base 2, illuminates the dynamism of Xavante thought in view of the nation's
insertion in the Brazilian and global market economy at the turn of the 21 st century.
Nonetheless, the number 2 continues to be, for this Gê-speaking people, “the 2
of us together,” that is, the unitary value for all kinds of beings, human or not,
material or symbolic. Here, the Western concept of number, based on a one-to-one
correspondence, rings as a partial truth, or a “lonely self” - mitsi , the Xavante name
for the number 1.
Chapter 6: “The Color Red. When Human Rights Enters the Discourse of Xavante
Youth in Mato Grosso.” Fighting with flowers and fruits now tinted red by blood
spilled from the body of a recently assassinated elder is the underlying motif of
more than 50 colored pencil and crayon drawings Xavante children of Central Brazil
produced in 2003. The drawings were created in the wake of the summary execution
and decapitation of one of their elders, Joaquin Maradezuro, by a local soybean
farmer in April 2003. Joaquim was stabbed in the back, his body chopped into pieces
and hidden in an old sewage pipe while hunting on ancestral Xavante territory now
owned by Ernesto Ruaru, one of the largest soybean plantation owners in the region.
The reader is given the opportunity to interpret the eloquent narrative and powerful
drawings of the Xavante youth about Joaquim's assassination. The color red conveys
the people's theory of environmental justice, incorporating the language of human
rights into Xavante discourse.
The Epilogue to this topic conveys, in a nut shell, the contributions Indigenous
mathematics have made to mathematics education worldwide.