What is the most important thing that history can teach us?

There are many things one can learn in a history class. The questions is, "What will be the most relevant or important thing?" History teaches you the values, beliefs, and traditions of cultures from long ago. Also, History gives us lessons from the past, so that we may learn from other people's experiences. History can make us proud of our past and inspire us to do great things in the future. History can help us make decisions based on careful evaluation of a situation. A good student of History can analyze facts in order to persuade people that what they say has merit. Lastly, History demands truth and proof that the story that is being told is the correct story. Which of these factors do you think is the most important thing that History will be able to teach you?