Dear all, In photo circles EVIL is currently used as an acronym for "Electronic Viewfinder Interchangable Lens" cameras, a new form of cameras that do away with the optical viefinder. Probably this is as firmly toungue-in-cheek as the use of the term "evil" in certain areas of category theory. And while I don't know if many photographers are offended by this term, this obviously is the case with some of our colleagues in category theory. While I'm sure that everybody agrees that the concept as such is important and worth studying, the ongoing dispute over the terminology seems to be rather counterproductive. Of course, one problem with mathematidcal terminology is that so many terms are overloaded by now (natural, continuous...) Any term borrowed from the realm of everyday life will carry certain overtones (and will irritate non-mathematicians). On the other hand, acronyms can come across a clumsy and an impediment to speach (ufl-functors). Maybe it is not too late to find a clever new name for the concept that does convey the negative connotations intended by the original adopters of "evil" without being so offensive to others (we don't want to wait 30 or more years before changing terminology, cf. the 2005/06 discussion concerning "cartesian" and "cocartesian"). Peter Freyd was always very inventive coining new terminology, even though not much of it caught on. Let me start by proposing "equi-unstable" and "precarious" as possible replacements for "evil". -- Juergen -- Juergen Koslowski If I don't see you no more on this world ITI, TU Braunschweig I'll meet you on the next one koslowj@iti.cs.tu-bs.de and don't be late! http://www.iti.cs.tu-bs.de/~koslowj Jimi Hendrix (Voodoo Child, SR) [For admin and other information see: http://www.mta.ca/~cat-dist/ ]
Dear Juergen, You wrote:
Let me start by proposing "equi-unstable" and "precarious" as possible replacements for "evil".
I agree that we should explore various options. Strickly speaking, there is no need for a new terminology since "non-invariant" has been used in the past and it is working pretty well. Let me draw a list of potential names. I have added a few: non-invariant equi-unstable precarious unstable fragile private I invite everyone to contribute to the list. Best, AJ -------- Message d'origine-------- De: Juergen Koslowski [mailto:koslowj@iti.cs.tu-bs.de] Date: lun. 27/09/2010 05:15 À: categories list Objet : categories: EVIL terminology Dear all, In photo circles EVIL is currently used as an acronym for "Electronic Viewfinder Interchangable Lens" cameras, a new form of cameras that do away with the optical viefinder. Probably this is as firmly toungue-in-cheek as the use of the term "evil" in certain areas of category theory. And while I don't know if many photographers are offended by this term, this obviously is the case with some of our colleagues in category theory. While I'm sure that everybody agrees that the concept as such is important and worth studying, the ongoing dispute over the terminology seems to be rather counterproductive. Of course, one problem with mathematidcal terminology is that so many terms are overloaded by now (natural, continuous...) Any term borrowed from the realm of everyday life will carry certain overtones (and will irritate non-mathematicians). On the other hand, acronyms can come across a clumsy and an impediment to speach (ufl-functors). Maybe it is not too late to find a clever new name for the concept that does convey the negative connotations intended by the original adopters of "evil" without being so offensive to others (we don't want to wait 30 or more years before changing terminology, cf. the 2005/06 discussion concerning "cartesian" and "cocartesian"). Peter Freyd was always very inventive coining new terminology, even though not much of it caught on. Let me start by proposing "equi-unstable" and "precarious" as possible replacements for "evil". -- Juergen -- Juergen Koslowski If I don't see you no more on this world ITI, TU Braunschweig I'll meet you on the next one koslowj@iti.cs.tu-bs.de and don't be late! http://www.iti.cs.tu-bs.de/~koslowj Jimi Hendrix (Voodoo Child, SR) [For admin and other information see: http://www.mta.ca/~cat-dist/ ]
What about "dangerous" rather than "evil"? (I also dislike religious and moral terminology for mathematics. I specially dislike the terminology "morally true", which I often hear, although I like the concept.) We frequently encounter dangerous situations in our mathematical paths, no matter how hard we try to avoid them, but if we know what we are doing it is ok. In this discussion about "evilness", what is important is to know that lack of invariance under isomorphisms is dangerous (and why this is so), and that you must consciously know how to properly proceed if your definition happens to be not invariant, be it for necessity, lack of a better idea, or mere convenience. MHE Joyal wrote:
Dear Juergen,
You wrote:
Let me start by proposing "equi-unstable" and "precarious" as possible replacements for "evil".
I agree that we should explore various options. Strickly speaking, there is no need for a new terminology since "non-invariant" has been used in the past and it is working pretty well.
Let me draw a list of potential names. I have added a few:
non-invariant equi-unstable precarious unstable fragile private
I invite everyone to contribute to the list.
Best, AJ
[For admin and other information see: http://www.mta.ca/~cat-dist/ ]
Of the choices offered here, I like "precarious", "unstable", or "fragile". I just thought of "risky" myself. Good, experienced mathematicians will know when it's okay to take "risks" (and will be aware of what the risks are). "Unstable" seems like a very sober choice, not too likely to ruffle feathers. I encourage anyone who cares about this issue to take a look at the current discussion at the nForum: http://www.math.ntnu.no/~stacey/Mathforge/nForum/comments.php?DiscussionID=1... You will see that opinions are divided even among workers in the nLab. Todd ----- Original Message ----- From: "Joyal, André" <joyal.andre@uqam.ca> To: "Juergen Koslowski" <koslowj@iti.cs.tu-bs.de> Sent: Tuesday, September 28, 2010 9:57 AM Subject: categories: potential names Dear Juergen, You wrote:
Let me start by proposing "equi-unstable" and "precarious" as possible replacements for "evil".
I agree that we should explore various options. Strickly speaking, there is no need for a new terminology since "non-invariant" has been used in the past and it is working pretty well. Let me draw a list of potential names. I have added a few: non-invariant equi-unstable precarious unstable fragile private I invite everyone to contribute to the list. Best, AJ [For admin and other information see: http://www.mta.ca/~cat-dist/ ]
Todd Trimble wrote:
Of the choices offered here, I like "precarious", "unstable", or "fragile". I just thought of "risky" myself. Good, experienced mathematicians will know when it's okay to take "risks" (and will be aware of what the risks are).
"Unstable" seems like a very sober choice, not too likely to ruffle feathers.
Mathematical terminology should not employ words that are merely value judgements, without relevant content. It doesn't make any difference whether they are offensive or inoffensive value-judgement words. This is not how we should choose scientific terminology. We are already cursed with vast over-use of the words "regular" and "normal" in mathematics. Roughly translated, these mean "the objects that I want to study" - other people may have very good reasons for studying other kinds of objects. ("Stable" and "sober" already have several meanings.) There is a problem here in that there is nothing in the education of a pure mathematician that teaches how to make a professional judgement. I never thought I would find myself defending software engineering (the religion whose creed it is that programs are better if their authors wear suits, draw diagrams and attend committee meetings) but when computer science students are subjected to this at least they learn that, whatever they do, they are making professional judgements. Since pure mathematicians do nothing similar in their training they are easily mis-led by the use of terminology that is based on value judgements. They just think that they are taking dictation from God. Even if there is a very strong argument in favour of a particular value judgement (as there may well be in the case under discussion) we should still not use words that have no other content, simply because we will want to make OTHER value judgements in future. The English language reportedly now contains over a million words. Can you really not find anything in this vast thesaurus (=treasury) that describes the situation more appropriately and precisely? There is less, not more, of an excuse if you speak French, Spanish or another language: English allows almost completely free immigration of words. Let's have a bit of imagination with language, please. Despite the abuse that I received for it here, I am rather pleased with my introduction of the words "prone" and "supine" for the two different orthogonal notions to "vertical" in a fibration. A word was needed to replace "open" for an object whose terminal projection is an open map, since subobjects with this property have a habit of being closed subspaces. The rich English vocabulary offered "overt", which means "explicit". Since I first used this word, it has emerged that this idea is very closely related to recursive enumerability, ie to having an explicit presentation, so this has turned out to be a very good choice of word. On the other hand, I regret introducing "bilimit" and "bifinite" in domain theory. In the case under discussion we need to distinguish between equal and isomorphic objects. In existing terminology, a category in which isomorphic objects are equal is called "skeletal", although I doubt whether this word ever gets another outing after the definition of a category and basic concepts therein has been given for the first time to students. So my suggestion is that you play around with skeletons, bones or even the Grim Reaper for something more suitable. Paul Taylor [For admin and other information see: http://www.mta.ca/~cat-dist/ ]
Paul Taylor wrote:
Mathematical terminology should not employ words that are merely value judgements, without relevant content.
Does "equi-unstable" have enough relevant content for you? Or do any of the proposals so far have enough relevant content for you? (I mean the pithy proposals contained in Joyal's list; there is always the longer "non-invariant under equivalence".) The quotation above seems to effectively summarize what the rant is all about; I think I can do without the judgment or projection that I or anyone else is taking "dictation from God".
Let's have a bit of imagination with language, please.
Yes, let's. I look forward to other suggestions as well.
So my suggestion is that you play around with skeletons, bones or even the Grim Reaper for something more suitable.
Thanks for the suggestion, but I don't much care for it if it merely evokes skeletal subcategories -- that is only one application of the concept we're discussing. Do you have a positive contribution you'd like to make, Paul? Todd ----- Original Message ----- From: "Paul Taylor" <pt10@PaulTaylor.EU> To: "Categories list" <categories@mta.ca> Sent: Saturday, October 02, 2010 1:43 PM Subject: categories: potential names
Todd Trimble wrote:
Of the choices offered here, I like "precarious", "unstable", or "fragile". I just thought of "risky" myself. Good, experienced mathematicians will know when it's okay to take "risks" (and will be aware of what the risks are).
"Unstable" seems like a very sober choice, not too likely to ruffle feathers.
Mathematical terminology should not employ words that are merely value judgements, without relevant content. It doesn't make any difference whether they are offensive or inoffensive value-judgement words. This is not how we should choose scientific terminology.
We are already cursed with vast over-use of the words "regular" and "normal" in mathematics. Roughly translated, these mean "the objects that I want to study" - other people may have very good reasons for studying other kinds of objects.
("Stable" and "sober" already have several meanings.)
There is a problem here in that there is nothing in the education of a pure mathematician that teaches how to make a professional judgement. I never thought I would find myself defending software engineering (the religion whose creed it is that programs are better if their authors wear suits, draw diagrams and attend committee meetings) but when computer science students are subjected to this at least they learn that, whatever they do, they are making professional judgements.
Since pure mathematicians do nothing similar in their training they are easily mis-led by the use of terminology that is based on value judgements. They just think that they are taking dictation from God.
Even if there is a very strong argument in favour of a particular value judgement (as there may well be in the case under discussion) we should still not use words that have no other content, simply because we will want to make OTHER value judgements in future.
The English language reportedly now contains over a million words. Can you really not find anything in this vast thesaurus (=treasury) that describes the situation more appropriately and precisely? There is less, not more, of an excuse if you speak French, Spanish or another language: English allows almost completely free immigration of words.
Let's have a bit of imagination with language, please.
Despite the abuse that I received for it here, I am rather pleased with my introduction of the words "prone" and "supine" for the two different orthogonal notions to "vertical" in a fibration.
A word was needed to replace "open" for an object whose terminal projection is an open map, since subobjects with this property have a habit of being closed subspaces. The rich English vocabulary offered "overt", which means "explicit". Since I first used this word, it has emerged that this idea is very closely related to recursive enumerability, ie to having an explicit presentation, so this has turned out to be a very good choice of word.
On the other hand, I regret introducing "bilimit" and "bifinite" in domain theory.
In the case under discussion we need to distinguish between equal and isomorphic objects. In existing terminology, a category in which isomorphic objects are equal is called "skeletal", although I doubt whether this word ever gets another outing after the definition of a category and basic concepts therein has been given for the first time to students.
So my suggestion is that you play around with skeletons, bones or even the Grim Reaper for something more suitable.
Paul Taylor
[For admin and other information see: http://www.mta.ca/~cat-dist/ ]
On 10/2/2010 10:43 AM, Paul Taylor wrote:
So my suggestion is that you play around with skeletons, bones or even the Grim Reaper for something more suitable.
Along those lines, how about "scythe" for the functor [-,1+1]: C^op --> C? In a Boolean topos this is just the (internal) contravariant power object functor, but more generally it tends to cleave objects into their connected components in a suitable sense. Vaughan [For admin and other information see: http://www.mta.ca/~cat-dist/ ]
Following up on Paul Taylor's suggestion to " ... play around with skeletons, bones or even the Grim Reaper ... ", Vaughan Pratt <pratt@cs.stanford.edu> offered:
... how about "scythe" for the functor [-,1+1]: C^op --> C? In a Boolean topos this is just the (internal) contravariant power object functor, but more generally it tends to cleave objects into their connected components in a suitable sense.
But "scythe"? A scythe is for cutting off stalks, wholesale. (A sickle is for cutting them off ... umm ... retail, perhaps :-) .) To "cleave" an object in two one might utilize a *cleaver*, or, more bluntly, a *wedge* -- but the resulting two parts are probably *not* in most instances "connected" at all, let alone "connected components": rather, they merely provide a binary coproduct decomposition of the given object. Cheers, -- Fred [For admin and other information see: http://www.mta.ca/~cat-dist/ ]
participants (7)
-
Fred E.J. Linton -
Joyal, André -
Juergen Koslowski -
Martin Escardo -
Paul Taylor -
Todd Trimble -
Vaughan Pratt