In a recent email exchange with a colleague, I have been discussing two aspects of metadata: naming conventions and taxonomies. Just as a reminder, “taxonomy” refers to the practice of organization and classification, and in this context it refers to the ways that concepts are defined and how the real-world things referred to by those concepts are logically grouped together. After pondering the email thread, which was in reference to documenting code lists and organizing the codes within particular classes, I was reminded of a selection from Lewis Carroll’s book Through the Looking Glass, at the point where the White Knight is leaving Alice in her continued journey to become a queen.
At that point, the White Knight proposes to sing Alice a song to comfort her as he leaves, and in this segment they discuss the song he plans to share:
- ‘…The name of the song is called "HADDOCKS' EYES."'
- 'Oh, that's the name of the song, is it?' Alice said, trying to feel interested.
- No, you don't understand,' the Knight said, looking a little vexed. 'That's what the name is CALLED. The name really IS "THE AGED AGED MAN."'
- Then I ought to have said "That's what the SONG is called"?' Alice corrected herself.
- 'No, you oughtn't: that's quite another thing! The SONG is called "WAYS AND MEANS": but that's only what it's CALLED, you know!'
- 'Well, what IS the song, then?' said Alice, who was by this time completely bewildered.
- 'I was coming to that,' the Knight said. 'The song really IS "A-SITTING ON A GATE": and the tune's my own invention.'
In this case, we have some definite confusion about semantics, naming and classification. I am going to try to disambiguate this a bit, so bear with me:
- There is a “thing” that is a SONG, which is “A-SITTING ON A GATE.” (See line 7)
- That SONG has a SONG_NAME, which is “THE AGED AGED MAN.” (Line 3)
- That SONG_NAME has a SONG_NAME_CALLING, which is “HADDOCKS’ EYES.” (Line 1)
- The SONG has a SONG_CALLING, which is “WAYS AND MEANS.” (line 5)
The frustration is evident in the interaction that Alice is unable to comprehend this rudimentary classification hierarchy and the difference between what that thing is, the name of that thing, what that thing is called and what that thing’s name is called. More about this classification in my next post.