All that we really know of ourselves and our world is the past; and all that we really know of the past is that part which has survived in the form of material objects. Only a small fraction of our history is recorded in literature, and literature is subject to the errors of human interpretation. Only the material specimens of human and natural history are indisputable; they are the raw materials of history, the undeniable facts, the truth about our past. Conservation is the means by which we preserve them. It is an act of faith in the future.