In the world that I am building there is what amounts to a militaristic application of psychohistory. Advanced mathematics are used to make tactical forecasts, and like the psychohistory upon which I based the concept, it works best on a large scale.
Predictive modeling is the closest real science that I know of to psychohistory. Before I turn to handwaving and otherwise making stuff up, I decided to ask the question: In what way can predictive-modeling be applied to warfare.
This kind of tech could be used for a short-term advantage. And it might even be decisive if you strike hard and fast enough, and use it to take apart your enemy's defensive response. But consider what happens when they realize what's going on:
Friendly Expert: Sir, based on our analysis we expect a 95% chance the enemy will react with tactic A.
Friendly General: Excellent.
Enemy Expert: Sir, based on our analysis of ourself, we'd usually respond with tactic A, and they'll likely try to do this to take advantage of us.
Enemy General: Excellent. Set the ambush up here.
You see? Once people realize what you're doing, they will start reacting to the model instead of their own history. At some point you end up in a spiral where you're just trying to figure out how deep you want to go. Consider this Princess Bride scene:
Man in Black: All right. Where is the poison? The battle of wits has begun. It ends when you decide and we both drink, and find out who is right... and who is dead.
Vizzini: But it's so simple. All I have to do is divine from what I know of you: are you the sort of man who would put the poison into his own goblet or his enemy's? Now, a clever man would put the poison into his own goblet, because he would know that only a great fool would reach for what he was given. I am not a great fool, so I can clearly not choose the wine in front of you. But you must have known I was not a great fool, you would have counted on it, so I can clearly not choose the wine in front of me.
Man in Black: You've made your decision then?
Vizzini: Not remotely. Because iocane comes from Australia, as everyone knows, and Australia is entirely peopled with criminals, and criminals are used to having people not trust them, as you are not trusted by me, so I can clearly not choose the wine in front of you.
Man in Black: Truly, you have a dizzying intellect.
The logic and double-think rapidly spirals out of control, and you lose most of the advantage from the technique. Do you choose tactics based on psychohistory? Or, knowing your opponent knows you use psychohistory, do you react to what you expect them to try and do to trap you? Or do you go deeper and deeper? There's no right answer - if you go down ten levels and your opponent only goes down one, there's no guarantee you picked correctly. Their basic tactic might end up defeating yours, because you were counting on them using level nine logic.
I think the other answers give you a good idea of some of the problems with this approach but I wanted to provide a different perspective.
We already do this.
Game Theory
There is a branch of mathematics called Game Theory. In Game Theory, the goal is to figure out the best strategy/tactics to apply in a given circumstance.
Game theory is the study of strategic decision making. Specifically, it is "the study of mathematical models of conflict and cooperation between intelligent rational decision-makers."[1] An alternative term suggested "as a more descriptive name for the discipline" is interactive decision theory.
A classic question in game theory is called the prisoner's dilema:
Two members of a criminal gang are arrested and imprisoned. Each prisoner is in solitary confinement with no means of speaking to or exchanging messages with the other. The prosecutors do not have enough evidence to convict the pair on the principal charge. They hope to get both sentenced to a year in prison on a lesser charge. Simultaneously, the prosecutors offer each prisoner a bargain. Each prisoner is given the opportunity either to: betray the other by testifying that the other committed the crime, or to cooperate with the other by remaining silent. Here is the offer:
- If A and B each betray the other, each of them serves 2 years in prison
- If A betrays B but B remains silent, A will be set free and B will serve 3 years in prison (and vice versa)
- If A and B both remain silent, both of them will only serve 1 year in prison (on the lesser charge)
The problem is the best strategy depends heavily upon how you weight the different results. Different strategies would be "best" depending upon that weighting.
It also depends upon independent rational decision makers making the best choice for their side (e.g. religious fanatics can't be depended upon to make the rational best choice for their side) and or some people weight goals and objectives differently than others.
Military & Political Decisions
The US military and State Department use Game Theory to identify probably scenarios and determine best strategies to deal with those scenarios.
When Russia invades the Ukraine, the State Department has already considered this possibility and worked through a series of responses figuring out most likely out-comes for each different approach. When different situations happen they show the US President the different scenarios and results of each and this helps guide the President along a path of foreign policy (military and political) most likely to achieve his desired results.
Once again, we have not developed this ability to an analytic problem solving technique. Rather they provide guidelines about different approaches and their probable conclusions.
It depends heavily upon the "other guy" weighting the different results the same as how you predicted those results. He doesn't need to value them the same as you but if you guess wrong about his weighting, your results won't be valid.
Probably not very well.
In warfare it would likely be a little like the stockmarket: anti-inductive. I try to predict you as you try to predict me and whenever either finds a pattern that can be exploited the other changes things while you both actively attempt to mislead each other to poison the others model.
Your models are going to look a lot more like stock market predictions than clean predictions.
Not sure if I understand you correctly, but militaries have been trying make models of future at least since the invention of general staff. The logistics of modern armies require you to have some idea of where units will be and what resources they have well in advance of the actual events.
This means gathering information of the area of operations such as weather and road conditions, information about your own forces and the forces of the enemy, about your own objectives and the objectives and then planning in advance potential actions of own troops to achieve your objectives or to counter enemy actions. Including the actions that the enemy takes to counter your actions.
Obviously any competent general has been trying to predict the future since ancient times, but until armies became large enough to require complex infrastructure of logistics informal methods or heuristics were enough, no actual modelling was needed.
Like I said I am not sure if I understood your question correctly, so the above might not be directly relevant, BUT I'd assume any "predictive modelling" would be built on top of that existing system. So instead of some fundamental change you'd simply add flexibility and precision to what already is.
For example, when WW1 started mobilizing the German army was a complex operation relying on preplanned actions written and distributed well in advance of actual events without knowledge of circumstances. The planners had simply drawn the plans based on their best guesses of why Germany would mobilize for war and under what circumstances. When the war actually started Germans picked the one of ready plans with assumptions that were the closest to reality. IIRC, this actually locked Germany to attacking despite the political situation not yet really requiring it. Consequences were disastrous.
Modern militaries AFAIK avoid this by making plans that are more flexible with options that can be taken based on what actually happens.
Presumably predictive modelling would allow making such plans and modelling new options on the fly in a coordinated fashion. This would mainly mean that field commanders would never be really off-the-map and forced to try to second guess themselves or existing plans. Their job would be reduced to recognizing which available options correspond to actual events and implementing them. In theory this would reduce information load and make decision making more efficient.
The big question flavorwise is what level of command the modelling goes down to. There is a big difference between a division commander having access to this and platoon commanders being able to rely on the big brother. The first would be pretty close to modern day (division commanders already have support staff) but more efficient, the second would be quite different and would be poison to any modern army to face. Until communications break down, at least. Would be pretty good for irregular warfare against militants, maybe?
Other answers are already very good, but I wanted to add a few ideas (also, I'm not yet allowed to comment).
Warfare tactics and stategy are already predictive modelling results, e.g. on a battlefield, if you watch Braveheart: since their advantage is their heavy cavalry, we will prepare long spikes to break their charge.
A good tactician on a battlefield will anticipate his opponents reaction to his move. The same goes with chess: if I take that tower, what will be the reaction of the opponent?
Now, those prediction are based on knowledge of the forces of the opponent, ground and/or situation of the battlefield (or current war position), and (also importantly) knowledge of the character and previous behaviour of the opponent's leadership. This was mostly done in an intuitive way, but not so much scientifically modeled.
Recen mathematical development would allow to place all the parameters into the equation and run the prediction. Which would make it suitable to be used on a battlefield.
Now, were both sides equally fully and perfectly informed, the predictive power and advantage of equal models would be rendered null as illustrated by @Dan Smolinske's answer.
However, one can assume that not all parameters are fully known. Just as there are different economy models these days, there could be different tactics models, used by different factions. And not all the model parameters (I could imagine that there are a few dozens of them) not fully known. Following @Dan's example: our model of our own reaction shows that we are likely to employ that tactics. But our understanding of 'friendly general' is that he is not likely to take the obvious route. So what are our next possible moves?
Furthermore there are competiting objectives: what is our best attack scenario, what is their best attack scenario, how can we anihilate the enemy, how can we escape, how can we stand our ground and defend our positions, how can we limit our casualties, etc. And those may change in the course of the battle.
At the end, humans do take the decisions, interpret the simulation results and have to anticipate possible irrational behaviour of the opposing army. A scientific modelling gives you an asset, but does not guarantee a victory.
Let's assume that you can predict exactly what the enemy is about to do in a reasonable timeframe. Let's also assume that the enemy has the same capability, and can predict what you're going to predict and how you react.
This basically creates a "I know you know I know you know" scenario, which however is not necessarily an endless loop; you might find that it eventually converges into a stable equilibrium, and essentially predicts the result of the fight if both sides fight optimally.
If you can also use the same capabilities to gauge the best reaction, as opposed to the most likely one, you could essentially run a Minimax algorithm to determine whether you're winning or losing, and decide whether to engage based on that.
If, however, the prediction is not perfect, then the war becomes an intelligence battle. You can't game your way out by acting sub-optimally, because that's by definition not a better course of action. If, however, you only have a tiny ace up your sleeve, you can use that to throw off the enemy's calculation and have them get a wrong equilibrium (because even tiny changes mount over many iterations), thus forcing them to engage in a battle where they might lose.
Of course, they may do the same to you, so you're probably back where you've started in the first place.
Warfare is very much about information asymmetry. A small informational advantage can often be levered into a large tactical advantage. This is nowhere more obvious than real-time strategic games like Blizzard's Starcraft. Although Actions-Per-Minute (APM) is one of the primary metrics used to measure the strength of a player, arbitrarily fast clicking will not overcome a tactical mistake based on poor information. In the game, one must weigh whether to move forces to raid an opponent's base, or hold them back to mount a successful defense. Whether 'tis better to attack or defend depends on what the enemy is doing and planning on doing in the near future, so scouting is critical in the game, as in real life. Moving your forces takes time, so abandoning your base to go on offense at the wrong time might mean losing an outpost when the enemy is able to also retreat and defend because they know you are coming.
Ultimately, there are 3 levels of analysis which may be considered in a game like Starcraft. The tactical situation involves the question of: "What is the enemy doing right now, when he is in my view?" During a pitched battle, the enemy may deploy various tactics like activating special weapons, focusing fire on various targets, feinting, making surprise attacks from different directions, etc. Except for cloaked units, the information at this level is complete, and standard game theory can be applied to predict what an optimal enemy will do, and the optimal response. While humans develop an extremely high ability to execute well in this environment, a computer can likely do better because of "infinite APM", etc. A real army will not move as precisely as a Starcraft army, and thus, a real general will have more difficulty executing a plan. So knowing your own capabilities is almost as important as knowing the enemy.
Above the tactical level, we have "general strategy", or "the meta-game". This involves questions like: "How quickly should I develop technology vs. build units?" "When should I expand?" "How forcefully should I defend expansions?" These questions depend on what the enemy is doing, which requires scouting. And scouting cannot gather complete information, so predicting what the enemy is doing at this level is much more difficult. However, there are several "standard" strategies, from rushing to turtling which can be recognized by the choice of various actions (which buildings did the enemy construct, where did they place them, etc.). Which of these strategies is popular in any given month changes as top-level players try out new techniques and counter old ones. This shifting of high-level strategy is called "the meta-game". This is analogous to generals knowing about trench warfare or siege warfare or combined arms tactics, etc. They are high-level techniques which can be recognized on the battlefield (or the build-up to war) if you know what to look for. Although there are an infinite number of high-level strategies, the vast majority of them are bad ones (do nothing for X minutes/days/years, etc.). The few good ones are quickly discovered, learned, executed, countered, and evolved. Any good analysis needs to keep up with the meta-game against potential adversaries, or it will not be able to anticipate anything. The weakness of the meta-game is that the best strategies involve tight constraints. You need to build certain things in a certain order to obtain the optimal outcome. So they have a signature appearance which can be detected by the informed observer. There are branches in the strategies which give some flexibility, but all choices commit you to a dwindling number of final paths.
Finally, the best players in the world have personal styles which compete, merge, mutate, and become the meta-game. But because they are the major innovators, they are the ones to watch to find out what players in the lower leagues will be doing a month from now. So we move from anticipating enemy actions based on well-known strategies to making predictions based on the observed actions of a single well-known adversary. This is the top level of analysis. It is both the strongest and the weakest level of prediction. On one hand, players are victims of their own habits. This makes certain things they do predictable. This is as true of entire nations and armies as it is individuals. On the other hand, the best players are always trying something new. This makes them inherently unpredictable, which tends to defeat predictive analysis.
Now, how a "computational stratego" might aid a future military depends on who the enemy is. If the enemy is unknown and makes a surprise attack, all bets are off. If the enemy knows you and your weaknesses, they are likely to prevail (or they would probably not have attacked if they knew they had an informational advantage but would still predict loss). If the enemy is known but makes a surprise attack, then the tactical predictor can still help anticipate small-scale actions and advise on best counter-measures (retreat, fire weapons, maneuver, counter-attack, etc.). If the enemy is known but conflict is not started with a surprise attack, and disposition of forces is mostly known, then the strategic predictor can probably anticipate most likely actions (because again, there are only a few optimal strategies, for most forces). But if the enemy is known intimately, and a conventional war breaks out, then the enemy can probably be modeled with high precision, especially if they have attacked other adversaries with a consistent strategy.
At the end of the day, every human being is a predictive modeler. One could argue that this is, in fact, the very definition of intelligence: to predict the near-future and optimize one's behavior accordingly. So a science or a system to do this is not going to do fundamentally better than a good military leader, except that they may do so with less bias and perform precise calculations more quickly. It will not become emotional or stressed, or make impulsive decisions. Ideally, it will actually do one thing better than humans could: react to a surprise. After all, an enemy is only going to attack because they have overwhelming advantage, and it doesn't matter what you do, because they are forced into this position and have no better alternative, or because they can exploit an information asymmetry and hope you do not respond quickly enough.
If you can predict overwhelming enemy advantage, then you have no counter-move, so psychohistory is useless. If you predict that the enemy is cornered into a particular move, then further prediction is trivial. If the enemy surprises you with an informational advantage, then by definition, you cannot predict this move. Thus, fast reaction is better than prediction.
But at the end of the day, information is what wins wars. This is why the "shock and awe" strategy of modern US military doctrine calls for disabling command-and-control capability first. This is why an unarmed drone with a camera is a big force multiplier for ground-based fire teams. This is why a strong intelligence network is better than a bunch of ballistic missiles in silos. Israel has wreaked more havoc with spies and assassins than any country has launching ICBMS. Everyone talks about China's million-man army, but the country's hackers report to an army general. Which do you think is more powerful today? Prediction cannot discover the secrets that an adversary is actively guarding and developing; only espionage can. Psycho-history is really only useful for slow-moving, non-adversarial targets, like civilian populations.
But to the extent that the enemy is purely human-powered, a tactical predictor can probably anticipate faster than a human tactician, in the same way that computer-controlled anti-aircraft guns are better than human-controlled ones. But this is a very trivial level of prediction, and not really what we mean by psycho-history.
If you can both predict what the other will do, with various probabilities, and what the probable impacts are, wouldn't war be a lot simpler if we just had the psychohistorians run the war and inform the army of who needs to be killed. Would save a lot of time, effort and money.
See the Star Trek episode where this happened:
Helmuth von Moltke: No plan survives contact with the enemy. Chaos theory has shown that even a small change in strategy can lead to unpredictable consequences. Weather forecasts, one man in front of a column of tanks in Tiananmen Square... If your mathematicians win, it will not be because of their mathematics.
There isn't a science of warfare - there are only principles of war (see http://en.wikipedia.org/wiki/Principles_of_war). These principle are based on culture, and are only general guidelines. Sometimes it may be beneficial to violate one principle (like mass) to exploit another principle (surprise). Additionally there are differences between the principles (that address strategic issues) and principles for individual types on combat operations (in ambush planning the principles are speed, violence of action, and audacity).
With all of the alternatives and competing planning an AI or Psychohistory would have to deal with tremendous branching factor as alternatives and reactions are considered.
