This study compared Greeks with Chinese, from 8 to 14 years of age, on measures of processing efficiency, working memory, and reasoning. All processes were addressed through three domains of relations: verbal/propositional, quantitative, and visuo/spatial. Structural equations modelling and rating scale analysis showed that the architecture and developmental patterning of the various processes are basically the same in the two ethic groups. The Chinese clearly outperformed the Greeks in all tasks addressing visuo/spatial processing, from processing efficiency through working memory and reasoning, but neither in g nor in processes where the two groups have equivalent experience. This advantage was associated to the massive practice in visuo/spatial processing that is required to learn the Chinese logographic writing system. The implications for general theory of intelligence and intellectual development are discussed.