I've never mastered the Hindu squat, the squatting posture that people (both Hindus and Moslems and presumably Jains and Sikhs and so on) are capable of for hours, with seeming comfort. I am reasonably comfortable sitting cross-legged and surprisingly comfortable sitting in a lotus position. However, there is nothing comparable to the luxury of the back support you get when sitting in an actual chair.
This is, surprisingly, a more reliable indicator of "civilization" than even plumbing is. To prove the point, the British have lots of chairs, but have never mastered the concept that both hot and cold water can come out of the same tap.
