The place of both center posts and gable posts in Chinese architectural history corresponds to the munamochi-bashira ridge-supporting posts in Japanese architectural history. While center posts emerged as the result of the replacement of wooden posts stood upright inside with those cleverly combined with horizontal members, gable posts emerged from the gradual introduction of wooden members into exterior perimeter mud walls originally containing none. The difference between the former and latter reflects that in the origination, an ancient difference existing since the birth of architecture. This supposedly ancient yet present difference characterizes the architectural styles in northern China.