There's an old saying about those who forget history. I don't remember it, but it's good.

Those who don't know history are doomed to repeat it

History is important. If you don't know history it is as if you were born yesterday. And if you were born yesterday, anybody up there in a position of power can tell you anything, and you have no way of checking up on it.

One is astonished in the study of history at the recurrence of the idea that evil must be forgotten, distorted, skimmed over. The difficulty, of course, with this philosophy is that history loses its value as an incentive and example; it paints perfect men and noble nations, but it does not tell the truth.

If we do not learn from history we shall be compelled to relive it. True. But if we do not change the future, we shall be compelled to endure it. And that would be worse. Alvin Toffler

Those who cannot remember the past, are condemned to repeat it.” — George Santayana, The Life of Reason: Five Volumes in One

But how can we forget what we never knew?

Perhaps everybody has a garden of Eden, I don't know; but they have scarcely seen their garden before they see the flaming sword. Then, perhaps, life only offers the choice of remembering the garden or forgetting it. Either, or: it takes strength to remember, it takes another kind of strength to forget, it takes a hero to do both. People who remember court madness through pain, the pain of the perpetually recurring death of their innocence; people who forget court another kind of madness, the madness of the denial of pain and the hatred of innocence; and the world is mostly divided between madmen who remember and madmen who forget. Heroes are rare.

We all have history. You can think you’re over your history. You can think the past is the past. And then something happens, often innocuous, that shows you how far you are from over it. The past is always with you.

It isn't a matter of forgetting. What one has to learn is how to remember and yet be free of the past.

Most things are forgotten over time. Even the war itself, the life-and-death struggle people went through is now like something from the distant past. We’re so caught up in our everyday lives that events of the past are no longer in orbit around our minds. There are just too many things we have to think about everyday, too many new things we have to learn. But still, no matter how much time passes, no matter what takes place in the interim, there are some things we can never assign to oblivion, memories we can never rub away. They remain with us forever, like a touchstone.

History is the consequence not only of people’s actions, but also of their forgetfulness.

Only by not forgetting the past can we be the master of the future.

Those who fail to learn from history are doomed to repeat it.