Jung, Memories, Dreams, Reflections, p.356

It is important to have a secret, a premonition of things unknown. It fills life with something impersonal, a numinosum. A man who has never experienced that has missed something important. He must sense that he lives in a world which in some respects is mysterious; that things happen and can be experienced which remain inexplicable; that not everything that happens can be anticipated. The unexpected and the incredible belong in this world. Only then is life whole. For me the world has from the beginning been infinite and ungraspable.