Is a Pop-Tart a Sandwich? A Philosophical Investigation
Tags: Philosophy, Science, Food, Poptarts

By Eliza Melville

As you may have overheard, seen, or tweeted about, Pop-Tarts are at the jelly center of an increasingly popular debate. Is the Pop-Tart, which features a filling wedged between two conjoined pieces of pastry, a sandwich?

Naturally answers to this question depend on how one defines a sandwich. As some have argued, sandwiches are culinary objects composed of two pieces of bread or bread-like substance with different contents inside. Under this scandalously loose definition, a Pop-Tart could be a sandwich, and probably so could ravioli. As others have argued, Pop-Tarts most certainly cannot be sandwiches, since sandwiches must include two separate (not joined together) pieces of bread, in a classic sandwich shape, with layered substances inside. Of course, this definition conflicts with New York State’s own definition (for tax purposes), which categorizes a hot dog, and it’s conjoined pieces of bun as a sandwich.

Things have gotten serious enough that we now need visual aids, like the Sandwich Alignment chart found here which plots sandwich definitions along a spectrum from the Lawful Good definitions (the sandwich purists) to the Chaotic Evil definitions (Pop-Tarts are sandwiches!). But in the many layered taxonomy of stuffed carbohydrates, there are also lots of other categories into which Pop-Tarts could fit: pastries, flattened pie, stuffed toast, or some other monstrous thing entirely.

Luckily for us, there’s an entire science of classification that can help us sort this problem out. It’s called taxonomy. Unfortunately for us, this science of classification isn’t nearly as orderly as we might like.

While the intensity of Pop-Tart debate may seem a bit bizarre, it actually goes all the way back to Plato, Socrates, Aristotle, Diogenes the Cynic, and other Greeks. Not that Plato was writing about shelf-stable foods, but he and his fellow philosophers liked incessantly arguing about how to label things, much like internet-dwellers love to argue that Pop-Tarts are, in fact, a kind of ravioli.

Plato believed the world was composed of groups of things with shared essential traits (traits that are essential to who they are). But for Plato and all future taxonomists, it’s important to accurately track and come up with the most valid, demonstrable, and real groups possible. Rather than hacking up the world into categories like, “things that are cerulean blue’” and “historical events after season 1 of The Bachelor,” which seem pretty arbitrary and unscientific, Plato famously suggested that documenting and categorizing the world was more like “carving nature at its joints.” This rather grotesque phrase became the way of speaking about the relation between nature and taxonomy: as if something called “nature” had natural and obvious joints, like bones in a body that connect but are distinct. All we have to do is recognize these clear boundaries and hack away. Easy-peasy.

Except, as it turns out, defining and categorizing things is incredibly hard. Inevitably and pretty much always, there will be at least one (but probably more) things that lie at the edge of your definition, fall outside or between categories, or don’t get included when they should. The Pop-Tart/sandwich debate is only a small part of the confusing world of food taxonomy. Is macaroni and cheese really just a casserole? Are eggplants fruit?

Another messy field is genre, as the divide between sci-fi and fantasy, for instance, can sometimes blur. But where we might view genre as something open for interpretation, and therefore messy classifications, we wouldn’t say the same of the sciences. We don’t typically understand scientific categories as flexible and open — though maybe we should.

In the life sciences, we typically take for granted the categories we use to describe and think about our surroundings. Not much thought is put into what constitutes a bacteria or a mammal. But occasionally, along waddles a furry, egg-laying, duck-billed, beaver-tailed creature from Australia — that makes us rethink how accurate, transcendental, or valid our categories really are.

But this is what happened when eighteenth century European taxonomists first encountered the platypus. Since Carl Linnaeus, the father of taxonomy, first coined the class term mammalia (which refers to all species whose adult women lactate), mammals were defined as being warm-blooded vertebrates who have hair or fur, feed their children milk, and give live birth (instead of laying eggs). Then up popped the platypus, which checked most of those boxes except the live birth — it laid eggs. Famously, this taxonomic rebel so confounded scientists that they thought it was a practical joke, a Frankensteinian creature stitched together from different animals.

The platypus might have meant the end of Linnaeus’s taxonomy of life. But instead, and after much debate, the platypus precipitated a shift in the definition of a mammal, which now includes the fact that mammals typically, though not always, have live birth. Which might seem like a cop-out. Do sandwiches typically, but not always, contain two pieces of a carbohydrate embracing its inner deliciousness?

Exceptions to our categories require us to reevaluate both our definitions and the inflexibility of our categories. Sometimes exceptions can be accounted for, but sometimes things get a little more drastic.

Like the platypus debate, the Pop-Tart-as-sandwich debate is really a debate about how useful taxonomies really are: it’s about how we define things and how strictly we think those definitions and categories should be applied. Taxonomies of life are useful. They’re like a shorthand that allows scientists to put things into sensible, easily studied groups without having to reinvent the wheel every time they encounter a new creature.

Naturally, food taxonomies work just like other kinds of taxonomies: they strive to provide definitions of different kinds of things and to organize them into increasingly specific subgroups according to fairly stable shared traits, so that each object has its proper place. As a consumer of food, this is useful. One is, or isn’t, in the mood for a sandwich. A menu would be generally useless if it just listened ingredients — say, flour, water, salt, vegetables, olive oil. Instead we need taxonomic assistance in determining if this combination of flour, water, salt, vegetables and oil will sate our desires. “A panini,” you might have to explain to a confused boomer, “is just a grilled sandwich.”

It’s a fact of all creaturely life — from cells to spiders, humans to humpbacks — that identifying patterns, establishing similarities, and grouping things together helps us predict things about the world that allow us to thrive. The big questions — and I mean monumentally huge — are: How fixed and stable are these categories really? And are these categories reflections of the way the world really is, or simply pragmatically useful distinctions?

If we understand plants as a category of living things that make their own food, what should we make of the ones that also catch their own meat? What do we do with the whole mess of slime beings and mushrooms that are closer to animals than plants (did you know humans share a common ancestor with fungi?) and whom nobody knows quite what to do with? And don’t even get me started down the microbial rabbit hole, because those little organisms are confounding all sorts of fairly established categories, from the way reproduction works, to how genes get transferred, to the way evolution works, to even what we mean by a biological individual.

And speaking of biological individuals, like you or me or my dog, Mona, exploring this concept is a great way to understand how things can exist between categories.

One would think that the concept of an individual is a pretty basic and unassailable fact of the universe. But one would be wrong, or at least partly wrong.

While it’s true that individuals do exist, it turns out the world and its creatures are too complex for a single conception of the biological individual to suffice. This has resulted in a labyrinth of definitions of what counts as a biological individual. Some of these definitions even contradict one another. You’ve got your genetic definitions (each individual has a unique genetic blueprint), your distinct boundaries definition (distinct in space), your immunological definition (which refers to whatever your body and immune system recognize as you), and the list goes on. If it seems wild that even such a seemingly simple concept would cost scientists thousands of hours of debate, welcome to the head-spinning world of taxonomy.

It may seem these definitions could tag-team without much conflict, but considering the following. By the immunological definition, it seems microbes become part of you as an individual even though they are separate species. And for that matter, the tongue-eating louse, a crustacean who eats out the tongue of a fish and functionally integrates into its body, would also count as an individual with its now tongueless fish (so there’s some biologically bizarre material for your nightmares).

And what do we do about clones, who are genetically identical but separate in space? The Portuguese man o’war is a particularly intriguing example because they are technically not biological individuals at all, but colonies (called siphonophores). A man o’war is a group of genetically identical beings (clones, actually) who are technically distinct, each performing their own function, but, just like a biological individual, they share a digestive tract, are functionally integrated, and cannot survive without one another.

It probably seems like we’ve gotten a bit afield of Pop-Tarts, but we haven’t really. Just like platypuses, portuguese man o’war, and tongue-eating crustaceans disrupt our clean-cut categories, it seems that Pop-Tarts and other tough-to-categorize foods might be lingering between otherwise pretty strictly defined categories. So potentially, as the sandwich alignment chart suggests, we might just need lots of sandwich definitions, even if many of them conflict with one another, if we want to be able to properly categorize all possible stuffed, glutinous, handhelds and finally get some sleep again.

In addition to the problem of things falling between or outside of categories, there’s another common problem with taxonomies. Definitions of a particular kind of thing (say, sandwiches or birds) typically rely on essential traits or groups of traits. In biology these groups of traits are often called property clusters. Yet most individual traits (bread with fillings, or beaks and egg-laying) are shared with entities outside the designated kind.

Take, for example, Diogenes’s retort to Plato in The Phaedrus. When the character Socrates claims that humans are “featherless bipeds,” Diogenes — who is pretty much the original troll — brings a plucked chicken and proclaims, “Behold! Plato’s human!” This is a trite example, but it exposed the limits of Plato’s claim that one could claim that such a broad and shared trait was definitive only of humans.

This is why the platypus initially posed a problem at the level of class — it combined traits that otherwise belonged to supposedly separate classes.

But the classification of food isn’t just for bored internet purveyors. It’s also a topic of real concern for lawmakers. In the famous tomato-gate of 1883, the U.S. Supreme Court formally declared that the tomato was to be considered a vegetable rather than a fruit. Technically, according to botanists and biologists, despite its striking (mostly culinary) similarities to vegetables, the tomato is a fruit because it is a seed-bearing entity developed from the ovary of a flowering plant. But according to the Tariff Act of 1883, tomatoes are categorized as vegetables, per their dominant culinary usage. Whether or not a tomato should count towards your daily serving of vegetables, we’ll leave to the nutritionists.

Probably the most famous example of the problems with taxonomy is what is commonly called “the species problem.” When you think of the basic units of biology, species is probably right up there with cells, DNA, and reproduction. But the definition of species you learned in middle school, called the biological definition (the one about sexual reproduction, gene transfer, and fertile offspring), is only one of many functional and widely used definitions. And, as you can probably by now guess, different definitions often conflict, making it very hard to treat species boundaries as fixed in the ways we once thought they were. Microbes, for example, more or less completely ignore the middle-school definition of species, and promiscuously exchange genes and traits all over the place, making typical species definitions pretty much useless.

So if we can’t even settle on a definition of a biological individual or fruit, let alone Pop-Tarts, it prompts the question: does the world really have carvable joints?

This is the question that has haunted philosophers for millennia. Instead of a unified resolution, there tend to be two major camps. First, there’s the camp that believes taxonomic categories are ontologically real, which is a fancy way of saying they believe categories refer to and capture different natural kinds who really are out there in the world and not just in our minds. “Mammal” isn’t just a category some guy made up because he liked pointing out mammae (breasts) wherever he could find them or because it sounded cool in Latin, but because there are actual essential traits that fundamentally connect all the beings now called mammals.

But when you treat categories as ontologically real and distinct, you end up with some problems. What do you do with entities that fall between groups? What happens when your definition doesn’t cover entities it obviously should, or when it includes entities it shouldn’t? And most importantly, what do you do with the definitions that conflict with yours? What does one do with the twenty five other definitions of biological individuals? If all of these definitions refer to real groups, things get a little clogged and chaotic, not to mention you’d end up with quite a few contradictions.

But instead of throwing the proverbial platypus out with the pond water, the other main camp suggests we see taxonomies as largely epistemological (concerned with knowledge) tools for thinking about and making sense of a world that is really too complex and messy for clean-cut taxonomies. This position understands definitions and taxonomies as crucial for scientific progress, creating experiments, predicting outcomes, etc., but doesn’t necessarily see the groups as actual, separate, essential kinds out there in the world. If we understand taxonomic categories as epistemological aids, useful for producing knowledge, it gets a bit easier to understand, for example, how each of the twenty six definitions of species could be useful at different times and for different reasons, or how Pop-Tarts might be both sandwiches and pastries. The epistemological perspective has the advantage of allowing one to espouse multiple definitions without getting tangled in contradictions. And it recognizes that the categories we use ought to be in the service of understanding a vastly dynamic, intricate, and complex universe, instead of hoping the world will conform to our existing categories.

In case you’re still not convinced that food taxonomies raise important questions, consider that there are even hotter debates raging today than Pop-Tart classification. As more Americans choose to reduce their animal consumption, and as more plant-based alternatives draw consumers, people are asking, “Can plant-based meats use the word ‘meat’?” Can Vegenaise or Just Mayo be called mayo if they don’t use eggs? And how do we classify drinks like soy, almond, and coconut milks, which have many of the same properties as the mammal milk (creamy, white, liquid, filled with protein and vitamins, used in coffee)??

Milk and meat lobbies are spending millions to influence the public and the FDA, in hopes of more strictly defining terms like “milk” and “burger.” Though the political, economic, and ecological stakes of this particular taxonomic debate are a tad higher than the Pop-Tart debate, it also mirrors the Pop-Tart debate in a lot of ways. In fact, that all of the above debates — from species, to Pop-Tarts, milk, and tomatoes — are just a microcosm of much larger questions about how we understand the world, how fractured and divided or continuous and flexible the world is, and how we can go about knowing and living better in it.