I’ve decided to attempt the first draft of a college-level textbook, writing it directly into my blog, bit by bit. Feedback and recommendations in the thread comments are welcome, either encouraging or critical. The first chapter is a mini-course in critical thinking for writers; the second chapter is a mini-course in rhetoric for writers. This post is part of chapter one. To have a look at other parts of the book, click here.
Concept 1.14. Binomial Definition. In the ancient Greco-Roman world, species identification meant looking at a thing’s matter and form and locating it within a hierarchical classification system by asking, “What makes this similar to other things—and what makes it different?” This is known as binomial definition, and was first formulated by Aristotle. For example, in defining humans, Aristotle saw us as animals—but with a difference: we alone can reason. Hence his definition of the human was: rational animal. The definition has a genus (what makes us similar) and a species (what makes us different). Contemporary taxonomists still use Aristotle’s technique of binomial definition, but they apply it in a more fine-grained way: Homo (man) is the genus (type) to which we belong—the category we share with genetically nearby, but now extinct, cousins, such as Homo neanderthalensis (“Neanderthal man”), and our species (our subtype or difference—differentia in Latin) is sapien, to be wise, echoing Aristotle’s “rational animal” definition. We are thus Homo sapiens—the wise animal.
Make your own binomial definitions. The lazy way to define a thing is to look it up in an online dictionary and quote it: “According to Webster’s Dictionary, a human is…” But that’s not very interesting, and if you do this, you pass up an opportunity to contemplate a word’s meaning for yourself. So let’s go back to Aristotle’s binomial definition of a human and think about it, seeing if we might generate other useful or interesting binomial definitions for what it means to be human.
Aristotle’s species component of a definition is sometimes referred to by the Latin word, differentia. And so, in definition, we have a generalization about a thing accompanied by a differentia–an observation that marks a difference. But humans are unique in more ways than just being rational–so we could, for example, define ourselves by one of our other unique qualities, such as laughter: humans could thus be defined as the laughing animal.
But the reason laughing animal may not seem quite as good a definition of human as rational animal is that one appears more essential to being human than the other. Or, if that is too strong a claim, one might say that laughter is implied among the behaviors we would expect from a rational animal, for many things are ironic and absurd, and one would thus expect laughter from a rational animal that recognizes this. Laughing animal, it is arguable, can be more readily subsumed under the more fully encompassing term, raitional animal. And laughing animal also may not work well as a definition of human because there’s some evidence of laughter-like behaviors in other animals, thus weakening the differentia. In any case, in seeking a good definition for a word, we want to identify, not just its unique properties, but its most essential qualities for our purposes (and to foreground those). It’s important to emphasize here for our purposes because that relaxes the energy around arriving at the single, objective, best definition for a word—which is really only arrived at in sentence context and authorial purpose.
Purpose in definition matters. So nothing immediately above should be taken as nixing laughing animal as a definition of the human, for if one is discussing, for instance, comedy, it may prove useful. It’s important to note that because our purposes in definition may vary, our definitions may therefore vary. Definition depends on what we mean to distinguish and make important. Thus, in Aristotle’s Nicomachean Ethics 1.13, he emphasized the capacity for reason as what distinguishes humans from animals. But Aristotle’s own definition shifted when he wrote in another context. When his concern was reflection on social behavior, he wrote in his Politics that “man is by nature a political animal.” That is, of all the capacities that animals have, only humans have the capacity for sophisticated politics. In this context, he singled out as our most essential differentia a high-level behavioral trait—our capacity and desire for socially navigating collective life in the context of city life (life in the polis–the city–as opposed to life in the oikos–the home).
So when we take it upon ourselves to define something, our individual purposes matter. There’s no one right way to define a thing. There are only insights as to how a word might be used or thought about in a particular context. In defining something, for instance, we may be shooting for an effect that is quite surprising, or we might say something a bit less obvious and concise—or even a tad more elaborate, such as the following: humans belong to the small group of self-aware social mammals that includes chimps and dolphins.
In the above definition, the genus is narrower than Aristotle’s: humans, rather than being broadly located within the hierarchy of living things, and most specifically within the kingdom of animals, are instead designated within the small group of mammals that are self-aware and social. So the genus in this definition of what humans are is: self-aware and social animals. But wait. Where’s the differentia? There isn’t one. There’s no differentia attached to this definition yet.
So let’s add one. What would make for a good differentia here? What distinguishes, in an essential manner, humans from other self-aware social mammals? In answer to this, we might say the following: humans are uniquely characterized by their capacities to reason, speak, and extend their influence and control over their environments via tools. So this brings us to a pretty good definition for what it means to be human: humans are self-aware, social mammals generally possessing the ability to reason, speak, and use complex tools.
Now we’ve got a pretty interesting binomial definition that can get us places (open up avenues for reflection and discussion). But what if we preferred not to define ourselves in relation to animals? There are, after all, other relations or hierarchies that we might wish to place humans in, and to do so would bring us to other definitions of what it means to be human. This is important to notice, for it reminds us that binomial definition is always relational and set into some broader conceptual hierarchy of our choosing.
Gods, angels, and aliens? Instead of in relation to animals, we may wish to define what it means to be human within the hierarchy of conceivably conscious beings (gods, angels, aliens, etc.), in which case we might arrive at an answer to the genus question in which we share key characteristics, not with gods or angels (who are, presumably, immortal and free of bodies and materiality), but with aliens: humans belong to the genus (type, group) of conscious beings that are carbon-based, solar system dependent, limited in knowledge, prone to error, and mortal. Unless aliens are quite far in advance of us, most conscious life forms beyond Earth are likely to share these characteristics with us. Hence the saying, “To err is human,” is also almost certainly true of many aliens (“To err is alien”). What makes us different is that we are on Earth, and so we might reach, after thinking about it some more, a full genus-differentia definition something like the following: Humans are Earth-bound and body-limited conscious mammals.
In the conceptual hierarchy of conceivable, conscious beings, the above definition distinguishes humans from gods (who are not Earth-bound or body-limited) and aliens (who are not of this Earth and have not evolved as mammals on our planet). In a pinch, we might make a genus-differentia definition that is really compact: Humans are conscious mortals. Or: Humans are conscious earthlings. But, really, this is inadequate because now we are being tapped on the shoulder by the chimps and dolphins (who are also quite self-aware and live on earth). So we might try again: Humans are conscious, rational, speech and sophisticated tool producing, mortal earthlings.
In relation to the gods and aliens, our mortality and Earth-boundedness come to the fore of definition; in relation to other social animals, our rational, speech, and tool-using attributes come to the fore. The definition is not boiled down to a two word binomial definition, but it is in the spirit of binomial definition, locating humans in relation to other things in terms of similarities and differences. So all this chasing after what a human is really reminds us that binomial definition is a way of arguing with yourself and others about what’s important. And notice that this definition of what a binomial definition is—a way of arguing with yourself and others about what’s important—also has a genus and a differentia! The genus is “a way of arguing with yourself and others,” and the differentia is “about what’s important.” But, of course, this definition needs more thinking about and work (which tends to be true of everything we value). The point is that, if you’re a thinker and writer, definition isn’t something you outsource to a dictionary; it’s something you do. There’s no one way of thinking about a word; there are only contexts for making distinctions. Thinking about binomial definition can help you navigate your way to a concise and efficient definition of a word that serves your purposes and communicates to readers what you take to be important—perhaps even most important. It helps you focus and to think clearly and precisely.
Writing 1.1.14. Think about a single word. What does it mean, really? Any word. Love, aging, sleep. What is it? Once you’ve got some thoughts going about the similarities and differences it has with other things or concepts, and the things you might group it together with, work your way to a binomial, genus-species (type-subtype; categorization-distinction) definition that is as precise, compact, and interesting as you can make it (without losing the essence of your definition). Keep distilling the definition down to as few words as possible until only what you regard as most important about it remains. Perhaps also then provide an example: “So I would include w as part of the larger category, x, possessing the differentia y, and here is a specimen (z, as an example) [Aristotelian genus, species, specimen]…”