I'm a junior in high school, and I want to go into some type of engineering. In APUSH, we learn about specific laws and battles and generals, and I just don't get the point. Whenever I ask someone this question, they reply with that bullshit "Learn history so you don't repeat it" line. So why should someone like me learn history.
Why is it important? To us historians it seems obvious that it is, but it can be hard to put under words.
A little exercise
One way to try to explain it would be the following exercise: Think about yourself and who you are. What is important about you? What defines you? Take a moment to think about this; perhaps write a little list on a piece of paper. Now imagine you know nothing about what happened before today. All that there is is you, as you are today, with no memories, no previous achievements, nothing. Go through the list you made earlier. How many things wouldn't be there? If the list is on paper, scratch out those things. What remains? For many people, the answer will be "not a lot". Your personal history has made you who you are. Similarly our shared history has made us (our community, our country, our world) the way it is. If we forget our history, we forget who we are.
A more fundamental response
Lots of people have thought about why learning history is important. They come to slightly differing conclusions, but they all come to the conclusion that is important. I'll list some different reasons why learning history is important below; the relative importance of these reasons can be debated, but all have been put forth as being of some importance:
Note that this is not an exhaustive list, nor is it a list which all historians would agree with. The points above have been adapted from Glöckel, Geschichtsunterricht (1973) and have been commented on, elaborated on, built upon many times since. The core is still same though: it's not so much the history itself that is important, but it is the way of thinking required for it and the understanding it brings that's important.
Disclosure: I previously posted pretty much the same answer here.
If you're looking for a very pragmatic answer — one that doesn't appeal to the fact that you do, indeed, learn things when you are learning about the past experiences of others and not just relying on your own, limited, experiences — the proper study of history involves the development of several very useful and applicable skills:
Non-fiction reading. For various reasons, much of the parts of high school and college education that are focused on reading skills are exclusive centered around fiction or creative writing. No problem with that, really, but I find it a funny thing to do given the lack of emphasis put into the reading of non-fiction — e.g., stuff about the world as it is or was. History reading is about reading for argument and evidence — it is about being able to evaluate claims to truth, even those being put forward about very subtle topics. This is a useful skill to hone in a world full of complex discussions about the future.
Non-fiction writing. Conversely, historical writing is about writing persuasive, evidence-based (empirical) essays on non-fiction topics. This is a useful skill as well. At the high school level, they are typically just trying to get you to basically understand the form of a persuasive essay (hence the emphasis on the "five part paper"), and that is a necessary if very dull evil, but if you keep with it, you'll find that history papers are really not nearly as dull as they feel at the moment. A good history paper is a creative exercise in and of itself, but an exercise more in arrangement than of language.
Non-fiction research. History papers require the marshaling of diverse forms of evidence and argumentation; of reading and synthesizing the work of other scholars as well as primary source evidence. It requires being thoughtful about sources and the kinds of things they do and don't say. This quickly gets you into non-trivial questions of how you know what is true and what is not, how we know anything "true" about the past. Of course, lots of fields of study require research, but I think history is one of the most flexible of the empirical disciplines — it requires you to not take anything for granted about how you know what happened, how you use that evidence to make an argument.
In short, history is (in my very biased view) the gem of the non-fictional (empirical) humanities. OK, you say, but I plan to be an engineer — why do I need any of these skills? Won't I just deal with numbers all day? (I teach history at an engineering school, so I get this question occasionally from my students.) The answer is: probably not, not if you want to be anything more than a cog in the machine. All professions these days involve a good deal of communication skills, and a good deal of complex thinking about "fuzzy" topics. Maybe you want to design bridges for a living — that's great. But to do that, you're going to have to deal with the complex intersections of government, commercial needs, waterways, funding, group organization, infrastructure, and so on. These are the kids of fuzzy, complex, subtle things that the skills taught by history are good at helping one take apart and understand.
Separately, history is the study of how the world got to be the way it is. If you plan on interacting with said world, much less changing it, it helps to know why things are the way they are. It can help you make decisions as a voter, it can help you make decisions as a citizen. The world is full of people making historical claims — often wrong ones ("the housing market can never fail! Reagan would have never negotiated with the Iranians!"). Being able to wade through these sorts of statements, and having a sensibility for whether they sound like the sort of thing that might be true or not, makes you a more capable person in general, and that can translate into all manner of advantages.
Now I designate the above as necessary to the proper study of history which is often not what they teach you in high school, and especially not what the AP tests typically measure. Why not? Because for a variety of irritating reasons, high school history is often treated as a memorization game, and the tests don't help with that. This is not (ideally) what college-level history is about, and not at all what historians do. If you find high school history dull and pointless (and I agree that specific battles and generals is pretty dull and largely irrelevant to your present and maybe future life), I will tell you that I felt somewhat similarly when I was in the same position (the most you can say for it is that ideally it gives you some shared cultural literacy, so that when someone says "Jackie Robinson" you know who they are talking about). I would just emphasize to you that you should give it another shot in college — find out who is a good history professor wherever you end up, and go in with an open mind. You will find something much more rewarding waiting for you.
The study of history is great and nearly bottomless in its topics — it covers everything that ever happened, there's something for everyone there! High school courses in history, well, they often miss the mark.
I think one underrated thing the critical study of history does is challenge our own certainties about what is universal or essential in human nature, or even universal or essential to say, an ideology or a religion or a country. We often assume that people are essentially like ourselves, and they must value what we value. Doubly so when they are our own ancestors - people who read the same holy books and the same Constitution (if we are American) as ourselves.
But if we allow ourselves to study the past and the people if the past as things in themselves, we learn how different they were from us. They read the same Bible but interpretted it in an entirely different way - they had a different understanding of the Constitution, they lived lives different from our own. And if we open ourselves to just how different they are from us, we can maybe see just how malleable and changeable human beings are. Even stranger, these people who live so long ago by their own actions and -for their own reasons- in some sense brought about the world we live in. -Not- because they existed for the sake of us, or because they necessarily -wanted- the world we live in now to look how it did, but because their actions had consequences they could not forsee. Ours will too, someday. It is humbling but enlightening.
The short version, to add to the great answers already on offer, is that whether you know it or not you have learned history. You learned basic American history (or the history of whichever country you are from) merely by osmosis.
Some of what you learned was half true. Some was myth. A lot of important issues were, I would hazard a guess, entirely omitted. This allows you to be manipulated on matters of both domestic and foreign policy, because the roots of both are often steeped in centuries or even millennia of history.
We use history like scientists use line graphs: To study past results, understand where we are relative to where we came from, and attempt to project where we want to be in the future. If you are ignorant of history, you can be spoon fed the equivalent of Creation Science without even realizing it.
A person´s intelligence alone is not enough for them to be able to see through the dishonesty of interested parties who want to indoctrinate you with their very slanted version of history. How can you take something into account if you don´t even know it is a potential factor?
A key mistake people often make is that group A may omit a fact but its opponents, group B, should bring it up if it is really important. This isn´t true. Both sides may have self-interested reasons to not bring up these issues in their public statements. A student of history would notice and factor in these telling omissions.
The study of history also helps you attain an awareness that many of the values and concepts which you hold implicitly and presume to be universal are in essence quite subjective. Mark Twain wrote that “Travel is fatal to prejudice, bigotry, and narrow-mindedness, and many of our people need it sorely on these accounts. Broad, wholesome, charitable views of men and things cannot be acquired by vegetating in one little corner of the earth all one's lifetime.” The study of history is functions much in the same way in undermining prejudices and narrow mindedness which we as individuals are often entirely unaware of. Its study, therefore, can help you become a better, more open minded, human being.
Everyone has so much to gain from studying history, or at least maintaining an interest in it, regardless which academic path you go down. I believe that an active interest in history actually makes people better citizens who are more informed and more able to participate in society. This is primarily due to the development of a fantastic set of skills that can then be called upon in a range of everyday situations. The kind of skills I'm referring to:
Reading, writing, critical thinking, and the ability to communicate complex ideas in ways that are tailored to the understanding of a specific audience.
An awareness of who you are, where you came from, and how your personality and values have been shaped by external factors.
The realisation that human behaviour is complex, is significantly influenced by the historical context in which a person lives, and that a persons motivations for doing something can rarely be explained in black and white terms.
I think one of the most significant benefits of having these types of skills is the ability to know how to think about complex issues that affect everyone. The ability to assess the historical validity of someones argument is an important inoculation against being manipulated for their political, social, or economic gain. Politicians love to throw around broad generalisations, governments love to exempt themselves and their actions from critical inquiry, companies love to appeal to stereotypes in their marketing. Having a reasonable grasp of the historical method or a good general knowledge of history can help you to avoid becoming someone who just 'takes everyones word for it'. You can go behind the headlines and hype and actually decide for yourself what you want to believe.
Another important result of having a good historical knowledge is that you can understand the world you live in. Too many people have very simplistic ideas about why certain things are a certain way and how they got to be that way. This of course has major consequences on peoples world view, which then flows on to values and beliefs. For example, here are some important questions that I personally wouldn't have a very accurate understanding of unless I had an interest in history:
Why are some regions of the world in perpetual conflict while others seem to only ever see peace and prosperity? Why is the middle east a hotbed of violence, and why is the Palestine/Israel question so complicated?
Why are so many European languages spoken outside of Europe? What has the impact of empire been on the colonised?
Why are some nations so wealthy while others are so poor? How has this dichotomy of wealth impacted how groups of people perceive themselves and one another?
Why do socioeconomic factors correlate with 'race' or ethnicity? How has the legacy of slavery impacted African Americans health, education and access to resources?
What are the discrepancies between the popular view of a nation, and how that nation actually behaves in world affairs? How do nations project power overseas and what impacts does that have on regional stability?
Speaking from personal experience, I've had countless revelatory moments where I've made a connection between what I'm reading with something else I've been looking at previously. Or I've learned something that is so central to the experience of a group of people, that I feel like I have a much greater understanding of the world.
Wars and generals and dates and places are the raw data of history. But when you incorporate things like revolution, empire, ideology, personal experience, then history starts to become something that is living and breathing and taking place right around you every day. And it is these events that are happening right now that will go on to shape the future world in which someone will look back on them as we do today.
In contrast to many of the voices here, I don't think that it is imperative that you study history. It's not for everyone. However, there are two ways that I think it can be very useful:
Whatever field you choose, it has a history. I know programmers who complain a lot that plenty of people out there coding have no sense of the history of OS or programming languages. Or, for instance, if you're a civil engineer in a city, knowing the history of a particular urban history is key.
Learning history isn't just about content: it's about being able to sift through sources and evaluate them. That's a skill that helps a lot of people, from academics to land surveyors.
So not all history is about whatever year Columbus did whatever thing. Once you get to college, studying history will be about a lot more than that.
And, yeah, if you are into politics at all, it helps to be able to tell history from myth.
Modern politics and law are also intertwined with history.
Take the 1st Amendment's freedom of religion clause - it harkens back to the rise of English Protestantism and the English Civil War, and the Founding Fathers' distrust of a state religion. It was based on the fact that the colonies had different religious make ups from each other.
From there, our modern interpretations are based on the writings of the Founding Fathers and the religious distrust of Catholics and other religious minorities over time.
The historical and legal study are intertwined - you can't have one without the other.
Well, I only have two good reasons to study history:
You should study history if you like history. Easy as that.
If you're into politics, you should study history. Knowing history gives you much more insight as to WHY things happen, and I'm willing to bet it would make you understand politics much more with a neutral point of view.