On River Street in Troy, N.Y. — the city where I was born and raised — there is a brownstone building that I’m particularly fond of. It overlooks the Hudson River and has a pair of commemorations on its front doorframe. On the right, an engraving recognizes the spot where the great fire of 1820 was halted. On the left, a worn bronze plaque reads: “Twas the night before Christmas when all thro’ the house…” (Many will recognize the popular Victorian poem credited to Clement C. Moore, but may not know it was first published in Troy in 1823.) Running my fingers across the stone, tracing the script and touching the edges of the raised metal letters, I realize how much I enjoy my connection to a city with a muscular past, made by hand, formed of brick, iron, stone, fire, wood. I realize, though, that coming up behind me are many who don’t necessarily share that aesthetic, and have no particular affinity for the difficult and dirty histories that accompany (post) industrial cities. Its materials of grit and brawn are clearly different from the new materials of photonics, which are flexible, additively manufactured, lab-grown, photoresponsive, and (with luck) nontoxic and renewable. These new materials swim, flex, and self-fold. Recently, Alphabet’s proposal for a smart city in Toronto — Quayside — has been in the news. It seems to have characteristics of both a sustainable city and a corporate surveillance city. Dangling sustainability in exchange for data mining isn’t, in my opinion, the ideal. I think we can do better. Of course, I am eager to see how photonic materials and technologies will be used to solve the pressing problems of waste and energy consumption. I am just as eager to see how design boards composed of more and varied voices will influence, plan, and build new infrastructures that demonstrate that we’ve learned from past mistakes. I’m glad I don’t live in Victorian society. But I am drawn to the lushness of material culture and the natural world woven together in Moore’s poem: bricks … shutters and sashes … hurricanes of dry leaves … mice, reindeer, and eagles … thistle down. It’s a reminder of the stuff of humanity that we make, touch, feel, haul around, and discard, and the stuff of nature that we need. I hope the designers of smart cities can find a way to minimize the great plumes of flotsam and jetsam we leave in our wake. At the same time, I hope new cities will represent greater inclusiveness and improved awareness of the needs of all forms of life. Have a fantastic holiday season, and to all a good night.