This is the second in a two-part series explaining the difference between similar notes you’ll find in the DDC. Part 1 focused on notes that describe what’s at a particular class: class-here and including notes. This part will look at notes that tell you to go to a different class: see references, class-elsewhere notes, and see-also references. Much like the relationship between class-here and including notes, these three give the same basic instruction, but there’s nuance to each. (Quick sidebar: What’s the difference between a note and a reference? Nothing! I don’t have a better explanation than that…)
A see reference is used for topics that logically belong in the class you find the note at, but for whatever reason is located somewhere else. Usually, it’s to give the topic a shorter number, or because the space it would otherwise go in is full or otherwise used.
For example, let’s look at 552.1-552.5 Specific kinds of rocks, which has five subclasses. I’m no geologist, but I remember from school that rocks are classified into three broad categories: igneous, metamorphic, and sedimentary. In the DDC, each of these has its own number under 552.1-552.5, as do two other categories: 552.2 Volcanic rocks and 552.3 Plutonic rocks. If you know your rocks, you might know that volcanic and plutonic rocks are subclasses of igneous. Sure enough, if you look at 551.2 Igneous rocks, there are two see references, pointing you to the respective numbers for volcanic and plutonic rocks. Since they’re see references instead of another type of note, that’s your cue that the topics logically belong together. Why did we give volcanic and plutonic rocks their own classes? Probably because there was enough literary warrant to do so.
Next up is the class-elsewhere note. They’re the workhorses of this type of note, and may be used for all sorts of relationships between topics. Check out that link to the Glossary for some of the cases in which we’d use one. The general idea is “you might expect this topic to be here, but it’s actually elsewhere.” Perhaps you could say the same for a see reference, but unlike see references, a class-elsewhere note doesn’t necessarily make any claims about the type of relationship between the topics.
For example, look at 374 Adult education. This number and its subclasses are about formal educational programs aimed at adults who already have some level of formal secondary and/or higher education. The first class-elsewhere note at 374 points to 331.2592 for on-the-job training. Since most people with jobs are adults, training given to workers often amounts to education of adults. But it’s different enough from what’s in 374 that it’s over in another discipline (in this case, labor economics). The second class-elsewhere note is for adult high school equivalency programs, such as the GED in Canada and the US. Since these programs involve secondary education, the DDC places them with secondary education even though they involve adult learners.
In both cases in the above example, you could imagine that if the DDC were being redesigned from scratch today, perhaps we would decide to put on-the-job training or adult high school equivalency programs with adult education. There’s enough of a relationship that we at least expect some classifiers might check there, so the class-elsewhere note helps steer you right.
Finally, the see-also reference. Unlike the other two notes in this post, a see-also reference links a topic to a class where it really doesn’t belong. There may only be a very loose relationship, or no relationship at all, between the two topics. Why bother noting these at all, then? It might be a case of homonymy, where the same or similar word has different meanings, or perhaps the topics are sometimes confused in everyday usage too.
There’s an example of a see-also reference at a recent development—the new number for conspiracy theories, 001.98. It has the note “See also 364.1 for conspiracy to commit a crime”. Conspiracy has a specific meaning in many legal and criminal codes. Like conspiracy theories, it stems from the basic definition of a conspiracy: two or more people collaborating on something in secret, often something nefarious. But people charged with criminal conspiracy may not have been engaged in any activity that’s the subject of a conspiracy theory, and not all conspiracy theories deal with activities that are necessarily criminal. From an editor’s perspective, I can imagine someone with a work on criminal conspiracy ending up at 001.98, perhaps from a keyword search, so I want to make sure they know to look elsewhere.
I hope this has been a helpful look at these similar types of notes. Knowing this, if you ever come across one of these in the wild that seems like it should be another type, feel free to reach out! You may well be right.
but every little helps – if you have an account/channel and wouldn’t mind… this link will take you straight there!
