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Should We Go With the 8-Quart Pot or the 12-Quart Pot? 

Date: 10/01/2026

Level of difficulty: Middle School/High School

Recently, I was asked this question. A family member was debating which size to get for cooking soups, preparing corn on the cob, and so on. Naturally, the first question that popped up in my head, and I suspect most others, was - well, what is a quart? Like anyone reading this right now, you may start trying to remember - is 1 quart equal to 4 cups, or is it 8 cups? Or maybe 1 quart is 16 ounces, yeah that sounds right, maybe? No matter what chain of thoughts were triggered in your head, inevitably your mind likely defined a quart in terms of some other unit (for example, cups or ounces or something else). But then that begs the question, what exactly is 1 "cup", or 1 "ounce"? Is it even possible to make sense of this made-up word "quart" without referring to some other unit of measurement? Hmm...These are interesting questions, assuming we don't run to ChatGPT or Gemini or some other robot. So let's explore.

The first one I'm curious to ponder is could I explain to an alien what a "quart" is without using any other units of measurement as a reference point. It would be difficult right? Imagine on our planet, thousands of years ago, or seconds ago but many many seconds ago, human apes roaming around, without the English language, I can't imagine them stumbling across anything in the natural world begging to be called "quart". But maybe, over time, one of these human apes became the chef of the community, and learned to perfect certain dishes. And for one of his recipes, there was the "perfect" amount of water needed for preparing his most beloved food. He knew the exact amount from repeatedly preparing the dish using a wooden pot the community had carved out for him. But when training others on how to prepare his dish, he couldn't just point at water and gesture to add it. Maybe one human ape would have added a drop, but another one might have interpreted "add water" and dumped in a whole bathtub of water. So the master chef knew he had to be more precise. He took his wooden pot, carved a little mark near the top, and communicated to his students to use "this" amount of water. If we pause this human ape story for a moment, we now at least know the purpose behind creating a word such as "quart". It helps us to describe an amount, or a volume, of something. So instead of the ape just pointing repeatedly to his carved wooden pot, for simplicity and efficiency, he could utter the word "quart" and other apes would immediately have a rough sense of what amount of liquid he was referring to. To be fair, he could utter any word, or sound for that matter, as long as that word/sound was the sole one designated for that specific amount of liquid.

With this in mind, maybe the best we can do then in our alien hypothetical where we are tasked to explain what a quart is without referencing any other units is precisely what our head master human ape chef did. Better yet, maybe beforehand, we could pour water from our chef's carved pot with the little mark on it into 100 containers all shaped differently. Some narrow and tall, others long but short, whatever weird shape we can think of. Then we tell the aliens this amount of water is what we call a "quart", and we have them pour the liquid from the 100 different containers into the chef's carved wooden pot, one at a time then emptying then repeating, so the aliens got a clear visual sense that a "quart" is this amount of water. No matter the shape of the container, once poured into the chef's wooden pot, the amount of water would always be the same and fill up right to the same mark. 

This does beg the question - can we be more precise then just referencing the human ape's carved wooden pot with a little mark on it? If I google "How much is a quart" what comes back is: 1 quart = 4 cups; 1 quart = 2 pints; 1 quart = .25 gallons. But than we are stuck in a recursive loop, because what is a cup, or a pint, or a gallon. More words, same problem. However, there is one definition, which yes, does use another unit for a reference point, but this time I can actually visualize and imagine what it physically looks like (whereas, I have no clear idea what a gallon is for example). That definition is, 1 liquid quart = 57.75 cubic inches. And as side-note, yes, I did have to google this, there's no way to deduce this on one's own, units of measurement are arbitrary and defined by humans. Now let's try and make sense of this: 1 liquid quart = 57.75 cubic inches. At first glance, we are stuck in the same predicament - what is a cubic inch. However, unlike the words gallon, cup, liter, and so on, a cubic inch is something easily imaginable by most people immediately. It's a three-dimensional cube that measures 1 inch tall by 1 inch wide by 1 inch long. Therefore, a "quart" is simply the amount of space that 57.75 of these cubes take up. Two liquid quarts would take up 115.5 of these cubes, and so on. Now I can confidently think about and imagine what a quart is because it is clearly defined in terms of a well-defined visual object. That's the difference between our ape's wooden pot with the mark on it, and a cubic inch, the cubic inch is a well-defined universal size that people on different sides of the planet can immediately agree upon and imagine in conversation, whereas the ape's wooden pot with the mark on it is not universally defined. Imagine the difficulty the ape would have on the phone trying to describe what a quart is to another ape on the other side of the planet using his wooden pot with the mark on it, it could be done in a sense, it would just be more challenging and require more time when compared to using the cubic inch definition. 

Someone reading this might be thinking "That's all well and good, but what's an 'inch'?". Fair enough. Does it ever end? I'll leave that for you to ponder...

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