What must happen in order for specialization of labor to occur ?

there is an explationation of this on a site called crash   course world history 1

answer; cattle ranching on the savanna,and forestry in the amazon;

the old way of life was represented by superstition, an angry god, and absolute submission to authority. the thinkers of the age of reason ushered in a new way of thinking. this new way championed the accomplishments of humankind. individuals did not have to accept despair. science and reason could bring happiness and progress. kings did not rule by divine right. they had an obligation to their subjects. europeans pondered the implications for nearly a century. americans put them into practice first.

what is the answer