Do you ever wonder why we study history, why learning about the past is a requirement in school? One of the most important reasons for studying the ways of our ancestors is that history repeats itself and learning about past mistakes helps us to avoid duplicating them.

David Rubenstein, author of The American Story: Conversations with Master Historians, discusses the importance of knowing our history and explains that, unfortunately, many Americans are not as knowledgeable as they should be. The author thought this problem was important enough that he started holding seminars about six years ago for members of Congress. The representatives, who should know the most about our history (aside from historians), are not immune to forgetting our past achievements and mistakes. Once a month, Rubenstein hosts a dinner at the Library of Congress so members can enjoy hearing a lecture from a historian.

Late Harvard historian and philosopher George Santayana said that those people who don’t remember the past are condemned to relive it. While certain aspects of history might be desirable, such as cleaner air and romanticized simpler times, who wants to go back to a time before electricity or indoor plumbing, when women were treated as property, disease was rampant, and even the common cold was deadly?

It’s not impossible to regress to a time before our own where these things were common. Medieval diseases such as leprosy, which had been all but forgotten in today’s world, are now making a comeback. California is now seeing a resurgence of these leprosy and the bubonic plague. The state has a large homeless population who find it difficult to access sanitation and health care services, and these people are vulnerable to contracting and transmitting these illnesses. The homeless situation in southern California is being considered the culprit for leprosy reappearing.

The U.S. has made great strides in eradicating diseases like as smallpox, the plague, and so on. Laws were put into place to protect us against contracting these deadly illnesses, such as mandatory immunizations for young children. Over the last few years, however, there has been an ongoing fight for parents who want to choose whether their children should receive vaccinations. Some say the injections cause other medical complications, while advocates are convinced that by not getting the vaccinations, these kids are promoting long-gone diseases to return.

In battles, generals and commanders often look to the strategies of their predecessors as they develop their own tactics. When faced with seemingly insurmountable odds, oftentimes looking back at historic battles and victories can provide the answers needed.