Egocentric spatial language uses coordinates in relation to our body to talk about small-scale space ('put the knife on the right of the plate and the fork on the left'), while geocentric spatial language uses geographic coordinates ('put the knife to the east, and the fork to the west'). This book studies child development in Bali, India, Nepal, and Switzerland and explores how children learn to use a geocentric frame both when speaking and performing non-verbal cognitive tasks (such as remembering locations and directions).
The need for improved mathematics education at the high school and college levels has never been more apparent than in the 1990's. As early as the 1960's, I.M. Gelfand and his colleagues in the USSR thought hard about this same question and developed a style for presenting basic mathematics in a clear and simple form that engaged the curiosity and intellectual interest of thousands of high school and college students.