A reply to Jaap's original arguments.
* Articles names at Wikipedia have to be unique anyway, so why not use the only ones that are always unambiguous?
This is a solid enough argument, it appears. It certainly appeals to the scientific mind, which hates ambiguity and likes clarity--qualities I like as well. So this is probably the main argument for the policy proposal.
* Scientific names avoid conflicts, since many common names often apply to different species. In such cases, one article gets the "good" name and the others have to be, um, different. How is this good for presentation?
You're saying, I believe, that there are species for which there are no common names
at all, except for a common name that they share with other species. Can you give an example or two? Isn't it almost always the case, however, that there are
also other common names for the varieties, subspecies, or different species that go under the same name? If so, one simply uses the name for the variety, etc., in question. Besides, this is a pretty rare problem, isn't it?
* Choosing between two or more more common names only on the basis of which one shows up more often in Google is arbitrary and unscientific.
Perhaps, but there is nothing arbitrary, or even unscientific, about preferring a common name on the basis of its popularity. To say that is simply to claim that common names are unscientific
because they are common. I'm not sure that's a very good reason to think that a name is "unscientific." In any case, if Google doesn't strike you as a good indicator of popularity, we might not use Google; we might consult some popular guidebooks, or--better--our own local experts (when they arrive).
* Selecting one common name for a species over all the others gives people the impression that it's more importance or more official than the others, even though that's not the case. An exception might be the AOU where they've tried to make certain common names for birds "official", but that's only for American species and even Wikipedia aren't following their lead.
You're inferring what people will infer about our placing an article about a species under a certain title. This is an very uncertain inference; so this is a very weak argument. The fact that my Field Guide to North American Birds makes use of common names for different birds does not make me infer that the other names they list are not also common names.
* Using scientific names avoids petty conflicts between editors: no more fights about Siberian Tiger vs. Amur Tiger or Puma vs. Cougar.
I suppose that's a very slight advantage--very slight, because the number of species with such competing names is relatively small. Moreover, we're going to have more effective means of settling such disputes on CZ.
* Common name tiles make category overviews pretty useless: just compare Category:True vipers with Category:Sharks at Wikipedia and you'll see what I mean.
If we don't use the Category feature at all, when giving an overview of a family (or whatever), then we can use whatever groupings we like, instead of relying on alphabetic. So on CZ I don't think this is going to be an advantage at all.
* Using scientific names for article titles can teach readers more about how organisms are related: "These names are weird, but look how the first names are all the same... maybe they're all related!"
This advantage applies not when looking at an individual article page, but at a page that has many different species names. Well, again, you can bring out this sort of information by constructing a page with it. I see nothing wrong with a page, or a section of a page, such as "True vipers in alphabetical order by scientific name". That does not require that we name the articles after the scientific names.
* Scientific names are universal while common names are not; people in one (English speaking) country may not be familiar with the common names in another.
This doesn't seem to be an advantage at all. CZ in English is...in English. We are not writing for non-English speakers. Therefore, we are under no obligation whatsoever, indeed we should find no advantage whatsoever, to make article titles more "international," i.e., non-English. We are writing in English. Dutch speakers can write for Dutch speakers when we start up nl.citizendium.org. I would not insist that they use international terms so that
I can understand
them better.
* Using scientific names for article titles promotes better continuity when linking with other articles inside and outside of Citizendium.
Again, a very minor advantage if an advantage at all. The point seems to be that if we are using a single unambiguous title for each species, then people will make fewer mistakes when they go to link to a species. First, not usually; second, if there is any question about what a page to link to is called, standard practice has us look the name up. How often will it be necessary to look up the name of species because their common names are ambiguous? Not often, I think. And you ignore the argument on the other side, namely, that even biologists have to look up the names of species when they know the common names very well. If you're worried about saving contributors time in making links, I'm sure the policy to recommend is that they should use the common names.
Decisions aren't well made by counting up the number of arguments on each side. It has much more to do with evaluating the importance and the certainty of the leading arguments. There is one argument, on the other side, that you didn't address here. It goes like this.
The purpose of an encyclopedia is to give people information they're looking for. It is far easier for people who need an article about a species to find that information if the article is titled by its common name--first and foremost because the common name is all that a person has. It is also easier for the simple reason, which must not be overlooked, that by titling an article with the scientific name of the species one gives the ordinary user the impression that the article is too specialized or scientific for him/her to be able to understand. I'm not looking for information about Panthera leo, I'm looking for information about lions. I wonder how much of your desire to organize articles about species by scientific name ultimately stems from a desire to create a beautiful system representing our knowledge of life. I can appreciate that sort of thing, because I am a system-builder myself. It's just that there is a difference between creating a fantastic, scientifically perfect system, on the one hand, and creating an information resource that is of maximal use to our audience, on the other hand.