Our past should serve as a foundation of experience that reminds us of some of the un-intelligent decisions we've made and also, of the intelligent decisions we've made. Both should be helpers in guiding us to making the right decisions at the right time based on whatever we are faced with.
Past is history and history is a living, breathing thing. We need the events of the past like tomorrow needs the hours of today to pass by in order to exist. Without yesterday there would be no today. Now, we shouldn't allow negative events of our past haunt us in our present state. That will just keep you bound to a time that no longer exists and ultimately set the stage for depression, anger, resentment, bitterness, unforgiveness and a host of other vices that contribute to becoming a victim of arrested development. Don't allow your past to bleed into your present and pollute your future. If they are negative things. But yes, I agree that learning about the past has great value, that information will equip you with knowledge of a time that can carry you to success in the future. Just be careful of what past issues you allow to surface or re-surface. Some things are not meant to be resurrected.