Question

Was agriculture the worst mistake in human history? I say no, but my history teacher says yes. I need a good argument.

Answer 1

It's likely he gets that position from this famous essay:

http://www.mnforsustain.org/food_ag_worst_mistake_diamond_j.htm

Probably the most solid counter-argument is that, while agriculture and civilization have indeed depressed the prospects of the majority of human beings below what they were in the hunter-gatherer societies that preceded them, it has also made possible technology and scientific progress -- and those are the ONLY long-term hopes for humanity to solve the very biggest conundrums of existence: how to genuinely ensure peace among men, how to ensure health and long-life for everybody, the conquest of disease and want, the freedom from the random cruelties of Nature -- possibly even, someday, the conquest of space, the meeting of minds different than our own (if there are any in this universe), and conceivably the conquest of natural death.

In short, it's a question of whether you think the really big triumphs are possible. If you think they are, the route would seem to inevitably run through agriculture and civilization and dense urban populations, because that's the only structure that produces surpluses that allow thinkers time and the equipment to think, and society the kind of institutional memory that lets multi-lifetime projects to get done. The degrading of the life of the average person may just be a price we have to pay for the ultimate triumph of the species.

That is, Diamond's point of view here is ultimately defeatist: he argues that we cannot really much exceed the boundaries of what chimpanzees can do -- so we might as well maximize our happiness within those limitations, which indeed probably points to the hunter-gatherer tribal society.