I want to know the answer to the following question:
In what work did Ferguson explain how humans advanced from a hunting and gathering society to a commercial and civil society without "signing" a social contract?
All the background I'm provided with is that "In his 1767 An Essay on the History of Civil Society, Ferguson uses the four stages of progress, a theory that was very popular in Scotland at the time, to explain how humans advance from a hunting and gathering society to a commercial and civil society without "signing" a social contract.". Is that enough to answer the question?