Incredibly beautiful, possibly because it maps so well to the mental model we typically use to organize knowledge in our heads. I don't know how we lost the folder/container vs. document/content iconography, and other things (like layout of items, sorting) during the shift to web applications.
Knowledge doesn’t neatly align to a nested hierarchy. Especially written knowledge.
Language is an imperfect means to convey knowledge, and people store that knowledge in subjective and highly personal ways.
You may mentally recall balloons within “entertainment” or “party”, whereas I might store that knowledge under “horror”.
Add onto that the massive focus on using graph theory to scale social networking technologically, and you effectively lose any motivation for rigid hierarchy.
A folder system doesn't have to be strictly rigid, you can still have "symlinks" so the same article appearing in different folders (aka labels if you can easily duplicate content inside folders, but you retain the nested, drill-down approach)
Wikimedia Commons has this feature. Editors can manually bless certain combinations of traits as "subcategories".
For example, https://commons.wikimedia.org/wiki/Category:Paintings_of_cas... contains the subcategories "Paintings of castles by country" (nested hierarchy), "Frescos of castles" (a medium), "Paintings of Château de Chillon" (a subject), and "Young Knight in a Landscape by Carpaccio" (multiple views onto a specific item). Each item may appear in multiple subcategories. As far as I can tell, the UI won't let you search for frescos of Italian castles (unless somebody's made a subcategory for that), or view all paintings of castles regardless of their subcategory.
I'm not very fond of this approach. I'd prefer for each item to have an unstructured set of tags ("fresco", "depiction of a castle", "depiction of Italy"), with automatic derivation of parent tags ("fresco" implies "painting") and the option to search by multiple tags. It should be possible to automatically discover tags which best refine a search, so that the UI can still suggest them to the user, as it does today.
> I'd prefer for each item to have an unstructured set of tags ("fresco", "depiction of a castle", "depiction of Italy"), with automatic derivation of parent tags ("fresco" implies "painting") and the option to search by multiple tags.
It's definitely possible to do this. IMSLP (a large repository of freely available sheet music, which differs by cross-cutting features such as genre, historical period, contributors (composers and others), instrumentation etc.) is MediaWiki based and has a plugin that does exactly that. These days the would probably want to host all the tags on Wikidata so that they can be multilingual and queryable out of the box, though.
Which is actually done on commons, it just isn't very popular (on images, click the structured data tab and then look at depicts) [admittedly i think a big part of the problem is is implementation choices and UI decisions].
That's only "depicts" claims and is nowhere near comprehensive. It doesn't even come close to matching what's currently stated using categories. Running searches on that data is also hard compared to what IMSLP gives you for their own system.
The Library of Congress uses both approaches, to an extent.
The cataloguing system uses a hierarchical classification, based on one originally developed by Thomas Jefferson, on whose initial donation the Library of Congress is based. This is known as the Library of Congress Classification, and is used to specifically locate a given title or work within the stacks, that is, each item has one and only one location.
There are also subject headings which are more tag-based, though also on a controlled vocabulary. A given work is given a (relatively small number) of subjects to which it's associated. These are not hierarchical, though of course the listing of subject headings itself follows a sequence. Unlike the classification, which assigns a single location to each work, the headings are a search aid to patrons searching for a set of related works within a subject heading, or facilitate branching of a search to possibly related subjects.
Tagging systems, especially ad hoc tags supplied by untrained users, are popular but tend to produce numerous issues over time. Not that formal systems (as with the LoC systems mentioned here) are immune to same. One feature of the LoC systems is that they've evolved processes for managing change over time. Examples would be terminology or classifications which are now deprecated, or of regions and polities which have changed or no longer exist (e.g., the Austro-Hungarian empire, the USSR), or of changes in underlying classifications (e.g., of chemical elements or of biological classifications, both of which have evolved significantly over the life of the Library of Congress).
The history of hierarchical information classifications is long and IMO fascinating, dating at least to Aristotle and his Categories, as well as numerous variants used in classifications of knowledge (such as Francis Bacon's) or encyclopedias, including Diderot's and Britannica.
Which isn't a hierarchy, it's a tagging system. The tags have some hierarchy but that's not uncommon. The distinguishing characteristic of "nested hierarchy" is that a particular thing should only appear exactly once in the hierarchy.
Since this is so terribly impossible most systems almost immediately make it possible for things to show up in more than one place, which means it's actually hierarchial tagging, whether or not the organizer(s) realize it.
You could also make a distinction based on how many tags things end up with; if it's almost always one, you could call it a nested hierachy with some exceptions, but if it's almost always more than one, and often much, much more than one, it's a tagging system. Even by that criterion that creates a spectrum rather than a binary distinction, Wikipedia is very much organized by tags and not hierarchies. I don't know what the average is but every Wikipedia page I've ever looked at the tags for has quite a few.
The ICD-11 has an interesting "nested hierarchy with some exceptions": each entry has a primary location, and secondary locations are implemented a bit like symlinks.
I agree, for some reason I have always alternated between wanting not just the universal search box but a browsable hierarchy to mentally run my fingers over and discover in a structured way.
We let go of the the manual index somewhere along the way since it doesn’t scale like search, obviously, but for the same reason I keep a library and enjoy traversing others’ private ones and visiting public ones, I keep coming back to browse.
Did you prefer the Yahoo/internet frontpage approach to google search though? I didn't, but I remember a time when it was a live debate. It has been interesting to see some sites like youtube or wikipedia evolve a quasi-hierarchical frontpage though.
I did. I made my own custom start page back in the day with frequently used searches, along with headlines, weather, stocks, etc. Instead of menus, it just divided topics using horizontal rules, much like an actual newspaper.
The way I usually frame this is: if all expertise could be eventually distilled into verbal form, then years of experience will cease to matter as it all could be replaced with a series of textbooks. Which we obviously know is not possible.
Good point, and I'm actually not sure that there is a clear dividing line. I expect that once we achieve capable world models and are able to analyze their internals, we'll find that the prediction mechanisms for purely physical and for verbal/behavioral responses to the agent's actions are at least partially colocated.
As particular motivation for my intuition, I expect that we had evolutionary pressure to adapt our defense mechanisms of predicting the movements of predators and prey, to handle human opponents.
The specific counterintuitive result is mentioned toward the end of the article, and I'm having some trouble understanding it:
> when analyzing average trends in groups of children, slower reaction times to the “Go” signal were linked to increased activity in many brain regions, including the default mode network
> However, when an individual had a slower reaction time to the “Go” signal, activity decreased in the default mode network — the opposite of the group-level pattern.
Now, I don't know anything about neuroscience or brain development, but hopefully I can explain the statistics in a way useful to you.
Imagine there are two groups A and B.
One group, A, has slower reactions on average and high average activity
The other, Group B, has higher reactions and lower than the Group A's activity.
Yet inside both groups the general trend is that if someone is slower than the average reaction of their group then they're also below the average activity for their group.
If we look at the overall means without distinguishing groups, slower reaction is correlated positively with higher activity (kids from group A have higher activity and slower reaction in general, which pushes the correlation upwards. As long as the relationship in Group B isn't too strong the upward trend from Group A can easily dominate overall correlation) but inside each group the trend is actually the opposite.
This applies pretty much every time you're comparing samples. If I understood your quote correctly, they're studying a child's reaction time vs activity level by comparing the same kid in different times. The same logic applies, a person can exhibit the opposite trend to the populational average due to the same mechanism above. This can be even more dramatic, because once you start looking at averages you start losing time dependency information.
More broadly (and more formally), multivariate covariance splits in within-group and between-group terms, so if the signs of the terms are different the magnitude of one can dominate the overall sum and flip the sign.
Hmm I think all these replies are overcomplicating things.
At a group level, some kids are slower at this Stop/Go task than others. The group difference appears to be this increased broad-scale brain activity: the slow group is overall more prone to distraction and daydreaming.
However, at an individual level, slowing down on the task means increasing your focus (and decreasing brain activity in irrelevant regions), regardless of whether you were in the slow group or the fast group. So the group-level difference is not necessarily as profound as it might appear, and applying "slow group" with too broad a brush means you're going to sweep up some kids who are naturally cautious and focused.
One way to think of it — I didn't read the article in depth so this is just an example — is in terms of overall individual differences in speed and activity level. Then, you could have slower persons having increased activity relative to faster persons, but it still be true that when a slower person had an even slower signal reaction, their activity went down, and when a faster person had a slower signal reaction, their activity went down as well.
It's a classic psychological phenomenon, where individual differences are obscuring time course patterns and vice versa.
Of course, this sidesteps the question of why (in the hypothetical example) the overall individual differences exist. Assuming those general individual differences are reliable and "real", you still have to explain why they are there, and if they predict significant outcomes, why they do, and so forth.
The message of the paper is good, although I think the press release (not surprisingly) overstates the significance of the paper. I think these kinds of issues have received a lot more attention in the literature in the last decade or so in neuroscience. It also sort of sidesteps a lot of the more thorny questions about truly person-specific patterns and how to determine when they're meaningful.
The answer may be agentic loops that keeps cycling through the same problem again and again until they land on a non-erroneous outcome. Some people boast having multiple such agents working in parallel on different problems, tending to one while another is processing, perhaps not unlike the movie mad scientist who runs around the lab throwing switches while laughing maniacally at the prospect of his impending success.
Do typesetters inexplicably change the meaning of the book or document being typeset? Do compilers alter the behavior intended by the programmer, sometimes in ways that are not immediately obvious? Did the invention of typesetters lead to investments so massive, that the investors had to herald the end of handwriting (no equivalent analogy for compilers)?
It reminds me of the guy who replaced his static blog deployment scripts with asking chatgpt to generate the html from his text based on a template, and said that he isn't sure that the llm isn't changing his writing but hopes it isn't
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