Rome? Why Rome? I arrive in China, attempt to ingratiate myself with the Han court. (I would be a white man, but would have full knowledge of Chinese and be an immaculate Confucian scholar. Hopefully that would be enough to get me close to the Imperial court, if just as an oddity.)
Somewhere in AD 2-5, the Yellow River changes course, causing massive suffering and discontent. I will have been predicting this since my arrival, as well as working tirelessly to reduce the damage done when things change. (Probably also betting heavily that it will happen.)
A major plot goes down in AD 3- the regent's son plots against the regent, with the regent winning. Ideally, I can use my foreknowledge of that plot to get a position of influence.
(If I can get there a year or two earlier, it's plausible that I could, by foreknowledge of astronomical and meteorological events, inventions, and knowledge of Confucianism, position myself to be the regent rather than Wang Mang.)
Once power is secured, economic and military technology is next. Rather than Wang Mang's unhelpful reforms, use the best of modern science to push forward the economy in every direction. Create an institute of naval architecture, and design ships capable of sailing to Rome; begin the creation of cannons; create outposts throughout the country that communicate by semaphore. The increased communication should make it easy to put down revolts (as well as knowing who will revolt, and why, anyway- ideally revolts can be stopped before they begin by solving their problems.) Implement the civil service exam a few centuries early.
The first campaign is against the valuable islands in Indochina, like the Moluccas. Outposts are established along the coasts of the Indian Ocean, giving me a massive naval presence. A eunuch Order of Navigators is taught the secrets of navigation, enforcing naval discipline as was done by the British Empire. Eventually, I'll have built up a significant naval fleet, supply line, and trading empire- which is topped off by sailing into the Mediterranean, and offering the Senate fabulous riches in spice, silk, and silver if they elect me Emperor of Rome. (If they refuse, starve the city by seizing control of the Mediterranean, cutting off grain from Egypt, offering amnesty and trade to any cities that align themselves with me rather than Rome.)
Then, focus on scientific development- start a eugenic breeding program, as well as collecting the best and brightest of several continents to a place chosen for its healthy climate and (hopefully) close location to Chinese or Roman power centers. Occupy the most ambitious by directing them to conquer nearby countries, giving them significant autonomy if they succeed (so long as they follow a few rules, mostly allowing me to hire away clever people).
As much as I hate this thought experiment, I will upvote you for subverting the classical Han dynasty -- and for implementing the civil service exam a few centuries early. Hopefully under you it won't turn into a sham so quickly.
A recent discussion post has compared the difficulty of an AI destroying modern human civilization to that of a modern human taking over the Roman Empire, with the implication that it is impossible.
The analogy has a few problems: first, modern humans don't have much greater raw intelligence than the Romans, only a bit more knowledge and tools; an AI would have a genuine intelligence advantage. Second, a high-tech civilization like ours offers many more ways for a genius to cause chaos than existed in classical Rome: it's more plausible that you can throw a few existing technologies together to create a superweapon than that Ptolemy could have done likewise, and there's no ancient Roman equivalent to hacking a nuclear launch system.
But taking over ancient Rome might serve as an interesting upper bound on the difficulty of an AI taking over modern civilization. And it's a theme of Harry Potter and the Methods of Rationality that rationalists should be able to come up with creative solutions to seemingly hard problems. So if Professor Quirrell offered it as an extra credit assignment, how would you take over Rome?
Here are the rules:
- You are thrown back in time to the year 1 AD. You can choose to arrive anywhere in the world, but your method of arrival cannot itself give an advantage (you can't appear in a flash of light in the middle of a religious ritual or anything).
- You do not start with Roman citizenship or any other legal record of your existence.
- You keep your original physical characteristics, including sex, height, and fitness. You will appear in period-appropriate dress of your choosing, and can't carry any artifacts with you. You may start with enough money to live a patrician lifestyle for a year.
- You are intellectually near-perfect. You know all human knowledge as of 2012. You speak fluent Latin (and all other languages of the day) and can orate as eloquently as Cicero or Demosthenes. You are a tactical genius of the order of Caesar and Napoleon. And you have infinite willpower and goal-directedness: aside from human necessities like sleep or food, you need never rest.
- You win if you either become Roman Emperor (and are acknowledged as such by most Romans), or if a state you control conquers the city of Rome. You lose if you die, of old age or otherwise, before completing either goal.