Knowledge is a resource in Aggressors: Ancient Rome. Knowledge is produced in the cities and is related to the sity size (bigger cities have higher production of knowledge). Knowledge is used for research of new technologies.
Investments into science, research and general education of the population will lead to new discoveries and faster development. Every discovery opens the door to a new one. Knowledge resource is produced in cities. Larger cities have higher knowledge production. However, growing cities have higher consumption of all other resources, so good planning is essential. Population growth can be regulated through birth rate control.