Multi-directional mappings in the minds of the Tsimane' - Size, time, and number on three spatial axes.

From early in life, people implicitly associate time, number, and other abstract conceptual domains with space. According to the Generalized Magnitude System proposal, these mental mappings reflect a common neural system for representing various magnitudes, and share a common spatial organization. In a test of this proposal, here we measured mappings of size, time, and number in the Tsimane’, an indigenous Amazonian group with few of the cultural practices (like reading and math) that spatialize size, time, and number in the experience of industrialized adults. On three spatial axes, the Tsimane’ systematically arranged imagistic stimuli according to their magnitudes, but they showed no directional preferences overall and individuals often mapped different domains in opposite directions. The results are inconsistent with predictions of the Generalized Magnitude System proposal but can be explained by Hierarchical Mental Metaphor Theory, according to which mental mappings initially reflect a set of correlations observable in the natural world.