Log or Linear? Distinct Intuitions of the Number Scale in Western and Amazonian Indigene Cultures

The mapping of numbers onto space is fundamental to measurement and to mathematics. Is this mapping a cultural invention or a universal intuition shared by all humans regardless of culture and education? We probed number-space mappings in the Mundurucu, an Amazonian indigene group with a reduced numerical lexicon and little or no formal education. At all ages, the Mundurucu mapped symbolic and nonsymbolic numbers onto a logarithmic scale, whereas Western adults used linear mapping with small or symbolic numbers and logarithmic mapping when numbers were presented nonsymbolically under conditions that discouraged counting. This indicates that the mapping of numbers onto space is a universal intuition and that…

• JS
  James S. McDonnell Foundation
• IN
  Institut National de la Santé et de la Recherche Médicale
• CN
  Centre National de la Recherche Scientifique
• NI
  National Institutes of Health