On Monday, my family celebrated the long weekend with a trip to our old end of Cambridge: a visit to a favorite bakery and a few hours’ playing and walking around at Fresh Pond. As we stood at one of the lookout points there, looking across the water, we were treated to one of those sights people pay big money to come and enjoy in New England this time of year: the dappled vista of a forest mid-transformation, with green giving way to red, orange, and gold, not only tree by tree but leaf by leaf.

But the beauty of autumn is a peculiar thing.

The beauty of fall foliage, after all, is both the revelation of the leaf’s true nature and the sign of the leaf’s impending decline and fall. The green color we see most of the year is something of a mask. It comes from the chlorophyll that allows the leaf to convert sunlight and carbon dioxide into energy, As the days grow shorter and cold weather approaches, the tree begins to retreat into itself. The “true color” of each leaf, beneath the uniform green flood of chlorophyll, is revealed. But the more of the leaf’s color appears—the less chlorophyll there is—the less energy the leaf is generating, and the closer it is to death.

And it’s the same with fall. Those of us who loathe the winter (that’s me) cherish every warm and sunny day, knowing it may be the last, such that a single seventy-degree day feels better in October than a week of them in June. It’s the knowledge that the winter is drawing near that makes a fall day’s beauty especially sweet.

In a world in which sweetness and sadness are often mixed together, we go through a thousand variations on this theme. Parts of our lives are peeled away to reveal truths about ourselves we’d never known before. Parts of our lives are made more precious by the knowledge that they are soon coming to an end. Parts of our world are made more beautiful by their very instability, by the fact that the leaf won’t stay a mottled orange-green forever.

Even so, that sadness is never absolute. The death of a leaf is not the death of the tree. This autumn is not the end of time. The seasons of our lives will continue to change. And even at the very moment the leaf falls, when its story seems to be at an end, new life is already being formed within the tree.

So “Glory be to God for dappled things,” as Gerard Manley Hopkins wrote,

… All things counter, original, spare, strange;
Whatever is fickle, freckled (who knows how?)
With swift, slow; sweet, sour; adazzle, dim;
He fathers-forth whose beauty is past change:
Praise him.