It would appear from what has been said so far that there are very definite requirements for a solution to the problem of history. It would seem it would have to be some world government, with no autonomy for nations in war-making nor any large-scale military science, with the powers to enforce universal non-aggression in the world government. But this is certainly not likely to come about, nor is it necessarily the case that a true solution would require this. In 1500 it seemed impossible that Athenian democracy made any sort of sense or could ever work on a large scale. At that time it was probably pretty reasonable to believe it would never work. But somehow democracy became the worldwide norm, and looking back we all suppose it was bound to happen that way and all history was leading toward it, though at one time all evidence told us it was probably impossible. Worldwide social dynamics are exceedingly unpredictable this way. I think world government of some sort could lead to a solution to the problem of history, but it would not necessarily require much loss of autonomy for individual nations or much enforcement power in the United Nations. Europe has been at war with itself through its inception; it is a mix of many languages and vastly different cultures. And yet now they have formed a union whereby they lose no significant autonomy, each is free to build its military, with no real enforcement power from the European Union authority. All this notwithstanding, they have very little to fear from one another now; events are such that they are perfectly confident that Germany will not be invading France, that England will not be bombing Italy and so on. For the foreseeable future, such ideas will seem absurd to Europeans. Something like this on a worldwide scale seems improbable right now, but give us a few hundred years, and it is certainly not impossible. All that requires a solution to the problem of history is not for nations to have no power to attack nations, but for nations to feel perfectly secure that no others will. This has not come about yet, but it is certainly not inconceivable that it will.