Which civilization is longest and continuous?

This is John Oliver Perry, academic, and long time observer of India. I am quoting him from the SASIALIT discussion group and find the following observation thought-worthy.

...it betrays such a passionfor Chinese culture and overlooks so much of
India's own unremitting and continuous efforts for civilized living (despite many
flaws and failures). Altogether, however, I suspect either the Sumerian-Iraqi
and/or the Arya-Iranian civilizations are the longest continuous ones... since
continuity itself is such a flexible term. Western efforts pale beside such
eons of human struggle....

Thanks for clarifying. Does it mean that Indian, Sumerian-Iraqi and Aryan-Iranian civilizations overtake Chinese and western civilization in the characteristics of length and continuity?

Anyone who can enlighten further?