Someone asks on Quora, How will you define nature and the environment? Here’s my answer.

Some people reject any distinction between “natural” things and “unnatural” things, saying that everything is natural because humans are natural and humans made the so-called unnatural things. But this doesn’t hold well. Fungus is made from old food left too long in the refrigerator; it doesn’t mean that fungus is old food.

I think another reason people reject this distinction may be that there’s no clear delineation between when a tool created by humans ceases to be a “natural” creation and starts being “unnatural” on the basis of its level of sophistication. (I.e., a simple tool by made by a smart, non-human animal is still considered to be “natural,” so it should follow that a tool just as basic and directly derived from the natural environment made by a human should also be “natural,” yet television sets are not considered to be “natural.” Where does one category begin and the other end?)

But I would say that the solution is simply to label those things that are obviously/intuitively understood to be sophisticated enough to be unnatural as “unnatural” and those things that are obviously unsophisticated, simple and directly derived from the natural environment enough to be natural as “natural,” and simple to not to worry about the fuzzy gray area in between.

We know intuitively what “natural” and “unnatural” mean, and there’s no reason to reach to logical extremes. And by reaching for a logical extreme in this way, saying that everything is natural, one completely removes any meaning and utility of the word “natural,” which is, of course, an error, because the words “natural” and “unnatural” exist in the language for reasons.

And the fact that words are defined according to common usage (i.e., a definition is descriptive, not prescriptive) also justifies upholding the popular, intuitive meanings of “natural” and “unnatural.”

To demand that there be no cases in which the difference between natural and unnatural is arbitrary (such as very simple and primitive tools, a chair made out of rock, etc.) for the distinction to have meaning is to misunderstand the distinction as being absolute, categorical or technical in nature. It’s not necessary for it to be such. The distinction is in characteristic per se, and in the vast majority of cases it’s obvious which is which.

Similarly, there is a continuum of brightnesses between nighttime and daytime, but that doesn’t mean that all time is nighttime or all time is daytime, or that the distinction between night and day is otherwise ill-founded.

One of the important uses of this distinction between “natural” and “unnatural” that gets wiped out by this appeal to logical extremes is within the subject of what is beneficial to do, create, consume, think, lingualize, or whatever—especially when working with the premise that nature/naturalness is generally or always more physically or mentally healthy than or otherwise superior to what’s unnatural, so that nature can be be used as our guide.

This premise isn’t assumed without good reason: we evolved within the context of nature for billions of years, so our bodies and minds are well-suited to exist and function within that context. Also, any given ecosystem itself evolved in such a way that it functions with balance, holism, wholeness and harmony, which are qualities that our mechanical, modular, brutish and simplistic technological creations don’t necessarily possess. The natural systems are able to utilize any and all natural principles, including ones living and magical enough that we can only dream of them, while the unnatural systems are only able to take advantage of the limited set of natural principles humans have been able to deduce.

And what is nature, exactly? I’d say it’s the set, or sum, of all things in our environment that are natural, as opposed to artificial. It’s the natural environment. You could also reason that it’s the source of our existence and, ultimately, of everything we create. (Nature being the ultimate, indirect source of everything we create doesn’t imply that everything we create is nature/natural.)

I would say that “the environment” is almost synonymous with “nature,” with a few subtle differences. “Nature” carries a connotation of involving natural principles and the overarching order of things and may include the totality of life and the universe, while “the environment” is more about the life forms and geological terrain of our world. It’s the collection of all the flora and fauna in the world and the larger systems in which they interact. Examples may include all ecosystems (or the biosphere as a whole), in addition to all aspects of their habitat, such as rocks, dirt and water. It’s the context in which the human species lives. I would say, colloquially, it’s contrasted to the artificial environments we’ve created for ourselves such as houses and metropolises.

Unlike with the word “nature,” I would say it is fair to use the word “environment” to refer to any part of the context in which we live, including our houses and cars, for example, because “environment” has a more general sense to it, but that’s not the same as “the environment.”