Stretched dough topped with a savory sauce and cheese

Pizza is a great topic for a definition, partly because everybody knows and loves it, but also because it’s so recognizable. But if it’s instantly recognizable, do we really need a definition? Honestly… probably not—pizza isn’t an idea that we can understand better by defining it. All that really matters is what it tastes like. If your favorite pie-shaped savory dish turns out to not be a “real” pizza, nothing really changes with a new definition. And because, in a sense, it doesn’t really matter, the definition of pizza is the perfect topic to dig into and explore. Maybe we can take some chances with a new definition to see if it makes a difference.

Most people are first introduced to the classic example of pizza: a flat round pie made from a lean bread dough topped with tomato sauce and cheese. The possibilities of what a pizza can be grow as we encounter more and more examples.

That’s how most dictionary definitions work too. They say it’s “A dish of Italian origin, consisting of a flat round base of dough baked with a topping of tomatoes and cheese, typically with added meat, fish, or vegetables.” This definition doesn’t try to capture the features that make a pizza unique; instead it points us to the classic example and lets us extrapolate from there. It also relies on “typical” features, which describe what pizzas are often like but don’t actually help define anything universal about them.

Relying on descriptions of the “typical pizza” means that everyone’s ideas of the definition are based on their own personal experiences. I’ve seen debates on whether a deep dish pizza is really a pizza or not, or if a pie without tomato sauce counts, or if there’s a difference between flatbread and pizza. Here we have a good opportunity to tackle a well-known subject and to explore some interesting opinions about how to make a definition for it.

I’ll start out with a controversial statement: a pizza is defined in part by savory sauce and cheese. Right away, some people are going to point out pizzas that don’t have sauce or cheese—I’ve even seen a restaurant serve “dessert pizza”—and say that the original definition can’t be right. I counter that those examples are exactly what convinced me of the importance of sauce and cheese in defining “pizza.” First, let’s consider an idea I call “definitional density.”

Some categories of words have a lot of definitions packed very close together, giving them a high definitional density. Imagine a car—how you would describe it? No matter what you’re imagining, it fits within some very clear definitions of “car.” Is it a coupe or a sedan or a hatchback or a wagon or an SUV or a convertible? No matter what configuration of doors or shapes, your imagined car fits into one or more of those groups. Because there are a lot of types of cars, and those types are defined very clearly, “car” has a very high definitional density. Every single possible iteration has a name with clear rules for what counts as part of that group and what doesn’t. A car can easily be an electric, two door, rear wheel drive, convertible, and we can easily say exactly why all those definitions apply to it.

Genres of stories are at the other end of the spectrum. They have very low definitional density. Pick a book—is it a mystery or a thriller? Well, it could be a little bit of both without clearly fitting into either, or someone could argue that it’s neither. Is it more sci-fi or fantasy, and where is the line between those? Some books are just “non-fiction” because they don’t fit into any other clear category. I call this low density because the definitions of the different categories are very spread out and their edges aren’t clear.

Topics that have high definitional density, like “cars,” have clear transitions from one thing to another. If you have a two door convertible and give it a fixed top instead, it’s now a coupe. There’s no point where those two overlap, and it’s clear which is which.

Ideas like genres of stories need more descriptions, because their boundaries aren’t clear and there are a lot of areas where no genre is the obvious choice. You could write a murder mystery with all the typical parts of that genre except the murder—it would have a detective, suspects, a slow reveal of facts and discoveries and then a big explanation at the end—but no actual murder. Maybe the victim wasn’t murdered. Maybe she was just in the other room the whole time and no one noticed. Is it a comedy now? Or just a plain mystery novel that happens to have almost all the characteristics of a murder mystery?

If you were to describe a story like this, you might call it “a murder mystery without the murder.” And that would probably be the clearest way to describe it, because stories have low definitional density, so there’s not another good option, no clear line marking where murder mystery starts or ends. Stories have a lot of potential for overlap with other genres.

Pizza, and a lot of other foods, are just like genres of stories in this way, because they have low definitional density. We don’t have a word that means “something that looks like a pizza but doesn’t have cheese” (maybe a “savory pie” would be a good description?). But most people would just describe it by starting with the closest definition that fits—“pizza”—and altering it by removing the cheese. If we call it a “cheeseless pizza,” we’re essentially saying, “There’s this thing that’s just like a pizza, but it doesn’t have the cheese.” It doesn’t fit clearly within the definition of any other kind of food, but it’s closest to the definition of pizza if we just make one change.

How did I convince myself of that? I imagine calling up a pizza place and ordering “a pizza without any toppings.” I’d get a cheese pizza with sauce, because cheese and sauce aren’t considered toppings by the pizza place; they’re part of what makes a pizza “a pizza.” If they thought that cheese and sauce weren’t part of the definition of pizza but were rather “typical toppings,” then they’d probably just make something like focaccia, a flat bread. I can’t imagine that ever happening without making it explicitly clear I didn’t want any sauce or cheese. So, we end up saying “cheeseless pizza” if that’s exactly what we want, because cheese is part of the definition of pizza and modifying that definition is the clearest way to describe something that doesn’t fit in any other category.

I’m happy with the sauce and cheese part of the definition, so let’s look at the dough. What turns regular dough into “pizza dough”? Most pizza dough is just bread dough with less yeast, so it doesn’t rise as high and ends up being more dense. However, I’ve seen a lot of very good pizza recipes that just start with regular bread dough. Those pizzas might end up being a little puffier, but they are clearly still pizzas.

So if it’s not the dough, it must be the shape, right?—except that pizzas come in lots of different shapes. Usually they’re flat and round, but what is it that makes deep dish pizza different than thick bread with toppings? I’ve baked a lot of breads and a lot of pizzas, and there’s two steps that show up in all bread recipes, but not for any pizzas—shaping and proofing. Bread is stretched and kneaded. Then, it’s made into a shape by folding it over, balling it up, or putting it into a pan, and by allowing it to proof, or rise, into its final shape. With pizza, we skip those steps: we knead and stretch out the dough, but once it’s flat, we don’t shape it again or let it rise. It’s topped right away.

The key idea here is that pizza is made with a stretched dough and that there are no more steps. I define stretching as making something longer while also making it thinner, and that would cover every kind of pizza dough I can think of. We’d have to accept that rolling dough out with a rolling pin or in a machine counts as stretching, and that pressing a dough into a deep dish pan is a way to stretch it as well, and I think those all fit. Starting out with a lump of dough and making it longer and wider and thinner sounds like stretched dough to me no matter how it’s accomplished.

We’ve got a pretty good definition for pizza now, keeping in mind of course that that doesn’t limit what we can actually make; it’s just a starting point to make it easy to describe the dish we’re making or eating. Usually I like to avoid making a definition too long. I wouldn’t want this one to end up as “a food of Italian origins that’s made with a stretched dough topped with savory sauce and cheese and often toppings and then baked.” A longer definition offers more chances for something to go wrong. For example, imagine teaching a little kid how to make pizza. You show them all the steps to make the dough and to top and bake it, and then you ask them if it’s a pizza. If the definition included “of Italian origins,” then the kid might not be able to accurately say whether or not the food they just made was a pizza. They’d know what it was made of and how it was made, but since they don’t know the entire history of the recipe, they couldn’t be sure if it matched the definition or not.

Or consider someone just happens to invent pizza independently again. Wouldn’t everyone want to call that new thing a pizza even though it had modern, non-Italian origins? And how would we tell this new “not really a pizza” apart from a “real” pizza? Would we have to ask the chef about the origin of her recipe? It’s true that pizza has Italian origins and that it’s an important part of its history, but that’s a description of pizza, not a definition. Of course, it’s possible to make a definition too short and miss an important piece of information. But if we’re convinced that we’ve covered the universal features, there’s no reason to add any extra detail. So, we have “a stretched dough topped with a savory sauce and cheese.”

Flatbread

What about flatbreads? This definition doesn’t do anything to distinguish between pizza and flatbread. Instead of making this definition longer, let’s determine what a flatbread is. By increasing the definitional density a bit, we’ll relieve the need to make this definition cover every iteration of flatbread in the culinary world.

There’s two pizza places near me. One advertises themselves as having “gourmet pizza,” but I’d describe it more as flatbread: it’s a little bit crispier than most pizzas and doesn’t have as much sauce. The other pizza place has flatbreads on the menu, but as far as I can tell, it’s classic pizza through and through. This raises an interesting point about writing new definitions: they’re really only useful if they can sometimes be used to correct a mistake. In the case of my local pizza places, they both probably have their own ideas of what pizza and flatbread are, but those definitions aren’t likely to agree and are probably inconsistent or even illogical. And fuzzy descriptions, like “a little crispier,” probably won’t convince anyone, and they definitely don’t make for great definitions. It’s fine to have your own definition of a word, but if you can’t use it to communicate with and sometimes even convince other people, then what’s the point?

Here’s the only consistent difference between pizza and flatbread that makes sense to me: pizza starts out with dough, and flatbread starts out with precooked dough. There are other characteristics that are typically, but not universally, different. For example, flatbread is often made without yeast at all and might have more creative or less traditional toppings. But some flatbreads do have yeast in the dough, and sometimes they have only tomato sauce and cheese, but they still somehow seem different than pizza. The difference is that the dough is precooked before toppings are added, which also explains why flatbreads might not have yeast. A dough like that, cooked thin and crispy is basically like making a cracker. Trying to make a pizza on uncooked cracker dough would be almost impossible without making a huge mess. The dough would just be too thin to hold together.

The qualities that I typically associate with flatbreads aren’t what define them though. Cooking the dough before topping it means that it’s likely to be thinner and crispier, but also sturdier. Because of this, the toppings can be a bit more inventive, either because they compliment the crispy cracker-like bread or because precooking it has made the base sturdier so it can support heavier toppings.

Maybe the point of flatbreads is to be thin and crispy with creative toppings. But if the only way to accomplish that is to precook the dough, then it’s the precooking that’s the universal feature that distinguishes them from pizzas. It also just makes logical sense—what would we call bread dough that was stretched out and cooked? We’d call it a flat bread. If you make a pizza using flatbread, we’d call it “flatbread pizza” or “gourmet flatbread”—or just “flatbread,” if we were already in a restaurant serving pizza (so as not to confuse the term with pitas or naan, which are also flatbreads).

We end up with pizzas being “stretched dough topped with a savory sauce and cheese” and flatbreads being “pizzas made with a precooked dough.” I don’t think the owners of the pizza place around the corner are going to see this and rewrite their menu, but maybe they’ll read it and think, “Hmmmm, you know what, that actually makes sense.” And that’s good enough for me.