025.431: The Dewey blog

Why are the disciplines within the 600s so disparate? An explainer

One question that people sometimes ask about Dewey is about why the 600s are a hodgepodge of seemingly unrelated topics. The caption of the 600 hierarchy is Technology, which makes it hard to understand how such disparate topics as medicine, engineering, cooking, child rearing, management, and construction would fit under one main class.

For the first 14 editions of the DDC, the caption for the 600s was Useful arts (as opposed to the 700s, labeled Fine arts). The categories of 600s in the first edition of the DDC are not too far removed from what exists currently in WebDewey; the divisions of the 600 hierarchy in 1876 were:

610 Medicine
620 Engineering
630 Agriculture
640 Domestic economy
650 Communication and commerce
660 Chemical technology
670 Manufactures
680 Mechanic trades
690 Building

As discussed in Philosophy of Technology and Engineering Sciences (page 47), the broad idea of "technology" was not a conceptual category when Melvil Dewey wrote the first edition of the DDC. Similarly, in a 1901 draft of the Library of Congress Classification, these topics were grouped together as "Useful Arts, Agriculture, Manufactures" in what would eventually become the "Technology" category.

In the contentious 15^th edition (1951), the caption of the 600s was changed to Applied science, while in the next edition (1958), the caption was revised again, to Technology. Some interim editions have listed the caption as "Technology (Applied sciences)," but the caption has remained Technology through the current edition.

To focus on just one part of the 600s, Melvil Dewey and his wife Annie were closely involved in the development of the discipline of home economics. (Melvil was very interested in economy and efficiency, founding the very first library instruction program in 1887 at Columbia under the name School of Library Economy.) At the Lake Placid Conferences on Home Economics, held annually from 1899 to 1908 at the Deweys’ resort, attendees worked to define the concepts involved in the new discipline and founded the American Home Economics Association. They proposed different names to represent the different aspects of the field (including "euthenics" and "ecology") and worked to combat the marginalized position of home economics compared to other disciplines (primarily because it was seen as inconsequential and women's work). The attendees of the Lake Placid conferences even proposed a new additional provision for home economics in the DDC within the 300s, because sociology and economics were seen as having more prestige than home economics. You can read more about this fascinating history in the 2004 article "Classification and the Definition of a Discipline: The Dewey Decimal Classification and Home Economics" by Anne M. Fields and Tschera Harkness Connell.

Understanding this history gives us greater understanding of just how malleable our conceptions of categories and disciplines can be, even though they can feel locked in place by systems like the DDC. Does knowing that the captions were once "Useful arts" and "Applied sciences" help make the disciplines located within the 600s make more sense? Would changing the caption of the 600s to Applied sciences (or something else) make it easier for users to find works? Let us know what you think!

This is the latest post within my series discussing frequently asked questions about Dewey. Previous posts have included: 

• How do the editors decide which concepts get a Dewey number? An explainer
• Why are the 200s so heavily focused on Christianity? An explainer
• What's the distinction between myth and religion in Dewey? An explainer

Flash exhibit: Crafting

Our most recent flash exhibit is about crafting! Lots of folks have turned to arts and crafts while sheltering in place. While patrons may not be able to access physical resources to help them learn or expand their knowledge while many libraries are closed, some libraries have virtual craft circles or provide access to online craft tutorials. This resurgence is a perfect opportunity to provide additional access in WebDewey for a few specific arts and crafts.

While some libraries put all their knitting books in 746.432 Knitting, the asterisk at that number provides the opportunity to add as instructed under 746 to provide more subdivisions for different aspects of knitting. Since I've been knitting a lot of hats in the past few months, I've created a new built number for 746.4320432 Costume--Knitting—arts, which can be used for hats, scarves, sweaters, gloves, socks, or any other article of clothing.

Some of the hats Violet has knitted during the COVID-19 pandemic.

Last year there was a great article in The Washington Post about libraries screening episodes of Bob Ross's "The Joy of Painting" while hosting paint-along events. If you're brushing up your own painting skills, you might be interested in works about painting nature. I've created new built numbers in WebDewey for 751.4543 Oil painting—nature and 751.42243 Watercolor painting—nature.

Kirigami is the Japanese technique of folding and cutting paper into objects or designs. Some libraries have put works about kirigami in handicrafts under 745.54 Papers, but the note there to "Class paper cutting and folding in 736.98" makes it clear that kirigami should go in that hierarchy. I've added a Relative Index term for Kirigami at 736.982 Origami to provide better access.

Finally, many people have taken the initiative to make homemade masks to help stop the spread of COVID-19. I couldn't find many books about sewing your own medical masks, but I bet we'll see at least a few being published in the coming months. One potential number for those works would be 646.5 Construction of headwear. You might see the RI term Masks—home construction at 646.478 Costumes and think that's the right place, but take a look at the other terms at that number: 646.478 is for costumes used for parties and theater, not for everyday wear (close attention is needed to spot the difference between "costumes" and "costume"!). Go a step up in the hierarchy to 646.47 Construction of garments for special purposes, and you'll see a note that says, "Class accessories for special purposes in 646.48". Following that note to 646.48 Accessories construction gives us a note that says "Class headwear in 646.5", which seems like the best place for works about sewing medical masks.

Pneumonia and COVID-19

Guest post by Julianne Beall

In the March 2 blog post COVID-19 (Coronavirus disease 2019), we said that we were not sure where to tell you to class works on COVID-19. Now we have updated WebDewey with three new subdivisions of 616.241 Pneumonia:

• 616.2412 Bacterial pneumonia
• 616.2414 Viral pneumonia
• 616.2416 Fungal pneumonia

We have indexed "COVID-19 (Disease)—medicine" to 616.2414 Viral pneumonia.

What about the non-respiratory complications of COVID-19? These two notes under 616.1-616.9 Specific diseases are relevant:

Class a work treating all the complications of a disease with the disease, e.g., all the complications of diabetes mellitus 616.462

Class a work that focuses on one specific complication with the complication, e.g., peripheral nerve disorders associated with diabetes mellitus 616.856

Thus, a work about all the complications of COVID-19 would be classed with COVID-19 in 616.2414 Viral pneumonia, but a work that focused only on renal failure as a complication of COVID-19 would be classed in 616.614 Renal failure.

The number 616.2414 Viral pneumonia can be added at various places in the 610s and elsewhere. For example, the interdisciplinary number and social services number for viral pneumonia in humans (including COVID-19) is 362.1962414. The number for incidence of and public measures to prevent viral pneumonia in humans (including COVID-19) is 614.592414.

Flash exhibit: Disabilities

The newest of our flash exhibits focuses on disabilities. This is a subject that is in constant flux as our cultural conceptions shift, so we try to keep up with revisions in the DDC as much as we can. Most works about disabilities are classed either in the 610s (medicine) or the 300s (cultural groups, education, or services to people with disabilities).

New works are always being published by disabled people with a wide range of topics. One that I noticed recently was not yet provided for in Dewey was works about sex and disability, so I've added a new built number, 306.7087 People with disabilities—sexual relations. This can be applied to many published works and new works like A Quick & Easy Guide to Sex & Disability (to be published July 2020).

Traditionally we've used the terms "deaf-blind people" or "blind-deaf people" in Dewey. However, most organizations around the world, including the World Federation of the Deafblind, do not use a hyphen in describing deafblind people. I've replaced those variants with the consistent use of the phrase "deafblind" in notes in multiple places. I've kept access to variants like Deaf-blind people and Blind-deaf people at in the Table 1 and interdisciplinary number (T1—0871 People with blindness and visual impairments and 305.9081 People with visual impairments), but in those and other places throughout the schedules, like 371.911 Students with blindness and visual impairments, we've used Deafblind people in the Relative Index terminology.

When works about disabilities are approached from a medical perspective, they should be classed in the 600s. I've added a new Relative Index term, Reading disorders—medicine, to 616.8553 Written language disorders to provide additional keyword and browse access.

I've also added the LCSH Autism spectrum disorders to 616.85882 Autism. In 2013, the Diagnostic and Statistical Manual (DSM-5) replaced terms like Autistic disorder and Asperger syndrome with just one term, Autistic spectrum disorder. Dewey has maintained terminology like Asperger syndrome and  Pervasive developmental disorders because they are still in use by the World Health Organization's International Classification of Diseases (ICD-10), and because works are still being published about those conditions.

While these were all relatively straightforward additions, while reviewing this subject I found one problem that I'd like to address. At 371.94 the caption currently reads Students with emotional disturbances, and there is a note reading "Including attention-deficit-disordered students, autistic students, hyperactive students." I don't think this caption is clear, and I’d like to find a librarian to help me work through a better way to describe these works. If you would be interested in assisting with this important project, please get in touch via email at [email protected].

Flash exhibit: Hermits

David Stanley / Flickr (CC BY 2.0)

Feeling like a hermit these days? Me too, and that’s what inspired our latest flash exhibit!

We had the LCSH “Hermits” mapped to 305.568 Alienated and excluded classes, which didn’t seem right. Yes, hermits are excluded from much of society, but they don’t quite fit with the other marginalized classes there. In the traditional sense, which is also the LCSH’s sense, a hermit is secluded for religious reasons. I moved the LCSH to 204.247 Asceticism in the religion schedules to reflect this. This would be the comprehensive number for religious hermits, or hermits in comparative religion, though works on hermits in specific religions would go elsewhere (e.g., 248.47 for Christian hermits, 297.446 for Sufi hermits).

Though sometimes treated as synonyms, there are separate LCSHs for hermits and recluses. Violet and I thought that was a better fit for 305.568, since living reclusively may be influenced by hostility from society. Of course, the distinction may come down to works in hand.

I also added the LCSH “Hermit crabs as pets” to the built number 639.67, under 639.6 Crustacean culture. Did you know that hermit crabs aren’t true crabs?

Finally, there’s something curious going on with the famous Hermitage Museum in Saint Petersburg, Russia. It’s the second-largest art museum in the world after the Louvre, and among the world’s top 10 most visited. It was already represented in a built number in WebDewey at 708.721, for art museums in Saint Petersburg, but you might not know it. We had the LC name authority record mapped, but following LC romanization rules, it’s “Gosudarstvennyĭ Ėrmitazh (Russia)”. You probably wouldn’t find that on a keyword search! I ended up creating an electronic-only Relative Index term “Hermitage Museum (Russia)”, which happens to be the Children’s Subject Heading form. We had started doing something like this with the names of world leaders where LC’s romanization diverges from more popular usage. There’s nothing wrong with keyword searching as an initial approach, so I hope this is helpful.

If you want to alleviate forced hermetism, here’s an ironic resource: last month, Apple released a one-take video that’s a virtual trip around the Hermitage Museum, shot entirely on a new iPhone. At a whopping five hours and 20 minutes, it’s great for slow TV fans or might be nice background material while working from home. It’s free on YouTube. Enjoy!

Flash exhibit: Cooking and baking

Last week we announced we'd be doing a series of flash exhibits, where we focus on a specific topic and publish small but hopefully helpful additions to the schedules. Since many folks are staying safe at home to prevent the spread of COVID-19, there's a lot of discussion of what everyone is eating. While the Dewey schedules already have a lot of provisions in these areas, we found a few more to add to help classify works about food and cooking.

First off, we've added the new number 641.5677 Islamic cooking, where we've added a Relative Index term for Halal cooking. This number was built using 641.567 Cooking for religious limitations and observances and adding the -7 from 297 Islam, Babism, Bahai Faith. We've also mapped Halal food to 297.576 Individual observances, along with Islamic dietary laws. Whether a work is classed in 641.5677 or 297.576 depends on the focus of the work, but hopefully it's clear which discipline the work belongs with: religion or cooking.

Since I've been craving sweet stuff, we added the LCSHs Doughnuts and Cupcakes to 641.8653 Cakes. Cupcakes obviously belong at that number, but you could make an argument for placing doughnuts at 641.8659 Danish, French, related pastries, and in fact, some libraries have classed works about doughnuts classed there. But more have used 641.8653. Maybe we need a new class number for doughnuts, but it would be a missed opportunity if the number didn’t have a zero in it for the sake of donut-shaped aesthetics!

Awhile back we also added the LCSH Smart cookers to 641.587 Steam and pressure cooking. That's the subject heading for Instant Pot and other "multi cookers," which are still enjoying a lot of popularity after being the hot new item a few years ago.

Are there other trends that we should be providing for? Do you see areas where additional numbers or revisions would be helpful? We’d be happy to work with you to make improvements! Get in touch at [email protected].

COVID-19 (Coronavirus disease 2019)

Guest post by Julianne Beall

We hope you are not yet trying to classify books about COVID-19! Why? Because we are not yet sure where to recommend that you class them.

Remember SARS? When we indexed "Severe acute respiratory syndrome—medicine" to 616.2 Diseases of respiratory system, we were following MeSH (Medical Subject Headings). The MeSH heading Severe Acute Respiratory Syndrome has Respiratory Tract Infections as the immediate broader term in the MeSH tree structure.

MeSH has not established a heading for COVID-19, but it has established a MeSH Supplementary Concept record. COVID-19 is mapped to Pneumonia, Viral. If the heading, when it is established, has Pneumonia, Viral as the immediate broader heading, we will index COVID-19 (Disease)—medicine to 616.241 Pneumonia.

The 616 number can be added at various places in the 610s and elsewhere, e.g., interdisciplinary number and social services number for respiratory tract diseases 362.1962, interdisciplinary number and social services number for pneumonia 362.196241; incidence of and public measures to prevent respiratory tract diseases 614.592, incidence of and public measures to prevent pneumonia 614.59241.

Stay tuned!

EPC 142A exhibits available

For the next four weeks, the Editorial Policy Committee will hold its electronic Meeting 142A via listserv. We welcome all comments on the following proposals, available on the Dewey Google Drive:

• EPC 142A-S28.1 286.63 Restoration movement--Specific denominations
• EPC 142A-S36.1 362.88 Victims of crime; 364.1 Criminal offenses
• EPC 142A-S52.1 Cartography, map making vs. Maps
• EPC 142A-S62.1 Sanitary engineering for rural and sparsely populated areas
• EPC 142A-S96.1 ANC presidents discussion paper

The committee will vote on the exhibits in the first full week of March. You can give feedback here, in the Google Group, or by email to [email protected] or an EPC member.

Interested in being a part of this process? Browse info for contributors, or join our webinar tomorrow. We'd love to work with you!

Making the switch to Intellectual disabilities

Most revisions that we talk about on the blog are large changes. The editors draft up formal proposals to revise Dewey; since February 2019, we've made those formal proposals public. (We make announcements about those periodically, but you can always see what we've got in the works at oc.lc/deweyexhibits). But we also make smaller changes nearly every day, which include things like fixing typos or adding new subdivisions for administrative divisions for countries around the world. (For example, last week we published revised class numbers for Norway, which recently went from having 19 counties to 10 counties.) We don't always talk about those changes, but they're important to keeping the DDC current; I wanted to share one of the small but impactful changes we've made recently. 

Last week I asked the Editorial Policy Committee to review my proposal to replace the term Mental retardation with Intellectual disabilities where it appears in captions, notes, and/or Relative Index terms. However, to ensure classifiers can find the correct terminology, I suggested leaving the Relative Index entries Mental retardation at 362.3 and People with mental retardation at T1--0874 and 305.9084. These will direct classifiers to the preferred terms Intellectual disabilities and People with intellectual disabilities. EPC approved those changes this week and they're now in WebDewey.

Why did this change take so long? One reason is that we have an international scope for Dewey. ICD-10 (the tenth revision of the World Health Organization's International Statistical Classification of Diseases) still uses Mental retardation, although the terminology will change with ICD-11, which will be in effect worldwide January 2022.

Why not just get rid of the term Mental retardation entirely? Well, because of the international usage in ICD-10, I worry that people won't find the correct place to classify works about intellectual disabilities if I don't provide cross references using the older terminology. In addition, I'm concerned that the Relative Index term People with mental disabilities could be confused for People with mental retardation, so I think it's important to keep both terms to give classifiers a heads up that these are not the same concept. In a few years, we should be able to revisit the decision and determine whether to remove references to Mental retardation entirely.

There is more work to be done in this area! I would welcome assistance from Dewey users to clarify terminology and ensure classifiers have appropriate guidance for the literature that is being published. For more information on contributing to shaping the DDC, please visit oc.lc/deweycontributors and get in touch via email at [email protected].

Food intolerance

Guest post by Julianne Beall

The LCSH "Food intolerance" has this scope note:

Here are entered works on difficulties digesting certain foods, which lead to physical symptoms. Works on immune responses to specific foods are entered under [Food allergy.] Works on the toxic effects of food containing naturally poisonous substances or toxic chemical residues are entered under [Food—Toxicology.]

As a subdivision of diseases of immune system, DDC has 616.975 Food and drug allergies, with notes:

Class here allergies of digestive system

Subdivisions are added for food and drug allergies together, for food allergies alone

As a subdivision of human toxicology, DDC has 615.954 Food poisons.

Where are medical works on food intolerance classed in DDC? At the September meeting, the Editorial Policy Committee reviewed and approved EPC Exhibit 142-S61.1 Food intolerance. Now in a subdivision of 616.3 Diseases of digestive system, we have added a class-here note at 616.39 Nutritional and metabolic diseases: Class here food intolerance.

Specific kinds of food intolerance are classed in appropriate subdivisions of 616.39. We have provided a new number, 616.39912 Celiac disease and other non-allergic gluten-related disorders, with the note: Subdivisions are added for celiac disease and other non-allergic gluten-related disorders together, for celiac disease alone. An example of a work that can be classed in the new number is Fast facts: Celiac disease.

We have also provided a new number 616.39982 Lactose intolerance. An example of a work that can be classed in the new number is The official patient's sourcebook on lactose intolerance.

We have relocated diet therapy that excludes a specific food or group of foods, diets to prevent a specific disease if the diets exclude a specific food or group of foods, from 615.854 Nutrition therapy to 613.268 Diets that exclude specific foods. For example, the number 613.268311 Wheat-free diet has the class-here note: Class here comprehensive works on gluten-free diet.

Works on gluten-free diets to treat celiac disease or to treat wheat allergy are both classed in 613.268311 Wheat-free diet. An example of a work classed in 613.268311 is Nutritional and analytical approaches of gluten-free diet in celiac disease.