In The Screwtape Letters, C.S. Lewis calls us “amphibians” because we are dual-natured: we occupy two worlds; we are bound by the flesh and the spirit. We go up and down through “a series of troughs and peaks.” (The Screwtape Letters, Letter VIII).This same undulation can be seen in marriage as well. We have our good moments (the beautiful sunset) and we have our bad fights (the darkness that follows). We reconcile (the sunrise) and the warmth of the noon-day sun is felt throughout our home and everywhere we go. Inevitably, the sun sets again and darkness follows. Up and down. Back and forth. What C. S. Lewis calls, the Law of Undulation.Is it possible, then, to just have the sunset with our marriages? Or in other words, can we buy the sunset by buying the field from which we have seen it?