In fact, while I’ve been making distinctions between natural scents and artificial ones, at this point in our planet’s story, many purportedly natural scents are already shaped by human intervention, including the banana. In the U.S. at least, there is only one banana cultivar in most grocery stories, the Cavendish banana, which didn’t exist two hundred years ago and was not widely distributed until the 1950s.

I remember the smell of rain as acidic in part because rain in my childhood actually was more acidic than contemporary rain. Humans were pumping more sulfur dioxide into the atmosphere in the 1980s than they are today, which affects the pH of rain. In my part of the world, rain is still more acidic than it would be without human emissions, so I’m not even sure that I know the smell of “natural” rain.

The challenge for scratch ’n’ sniff sticker makers isn’t, in the end, to mimic the natural world, which doesn’t really exist as a thing separate from humanity. The challenge is to imagine what combination of smells will make humans remember the smell of bananas, or ocean mist, or freshly mown grass. I wouldn’t bet against us finding a way to artificialize scent effectively—God knows we’ve artificialized much else. But we haven’t succeeded yet. When I open that ancient sticker book and scratch at the yellowing stickers curling at the edges, what I smell most is not pizza or chocolate, but my childhood.

I give scratch ’n’ sniff stickers three and a half stars.

DIET DR PEPPER

THE STORY OF DR PEPPER BEGINS IN 1885, in Waco, Texas, where a pharmacist named Charles Alderton combined twenty-three syrup flavors to create a new kind of carbonated drink. Notably, Alderton sold the recipe for Dr Pepper after a few years because he wanted to pursue his passion, pharmaceutical chemistry. He worked at the drug company Eli Lilly before going back to his hometown to head up the laboratory at the Waco Drug Company.*

Alderton’s soda probably would’ve remained a Texas-only phenomenon, eventually disappearing like so many other local soda flavors—the opera bouquet, the swizzle fizz, the almond sponge—had it not been for the dogged determination of Woodrow Wilson Clements, who preferred to be called “Foots,” a nickname he picked up in high school due to his oddly shaped toes. Foots, the youngest of eight children, grew up in the tiny Alabama town of Windham Springs. He got a football scholarship at the University of Alabama, where he was teammates with Bear Bryant.*

In 1935, when Foots was a senior in college, he started working as a Dr Pepper salesman. He retired fifty-one years later as CEO of a soft drink company worth over $400 million. By 2020, the Keurig Dr Pepper corporation, which owns, among many other brands, 7UP, RC Cola, and four different kinds of root beer, is valued at over $40 billion. Almost all of its products are some form of sweetened and/or caffeinated water.

Foots Clements succeeded because he understood precisely what made Dr Pepper significant. “I’ve always maintained,” he said, “you cannot tell anyone what Dr Pepper tastes like because it’s so different. It’s not an apple; it’s not an orange; it’s not a strawberry; it’s not a root beer; it’s not even a cola.” Cola, after all, is derived from kola nuts and vanilla, two real-world flavors. Sprite has that lemon-lime taste. Purple soda is ostensibly grape-flavored. But Dr Pepper has no natural-world analogue.