Wikipedia talk:Manual of Style/Archive (punctuation)

Making possessives

I've always followed the prescription of The Elements of Style for making a possessive from a proper name ending in s: One adds an apostrophe and another s. I don't have my copy ready to hand, but I believe the example concerned a royal tonsillectomy, in which the surgeon removed the tonsils and the copyeditor removed the s. (The authors condemned a newspaper reference to Charles' tonsils -- the correct form being Charles's tonsils.) I think the same rule would apply in the rare case of a singular noun that ends in s, e.g., the brass's polish would be correct. Of course, a plural possessive takes a simple apostrophe (the books' covers).

In the article on Bobby Fischer, I happened to notice a reference to his visits to his teacher, which read: "Fischer spent much time at Collins' house ...." Following Strunk and White, I changed it to Collins's. Another user promptly changed it back. Does Wikipedia have a policy on this burning issue? JamesMLane 16:20, 1 Jul 2004 (UTC)

Fowler says it is down to the pronunciation. "Charles's", but "Bridges'", because of the "-iz" sound.

Ruymoultor says I've always been taught that you don't add the "s" after the apostrophe because it is superfluous and for someone reading it they would pronounce it the same (so using Occam's Razor the shorter simpler version is used) but that's just me.

The Chicago Manual of Style sides with James on this one - even if the word ends in "s", the posessive adds "'s." Though, in classic Chicago style, it does note that "feelings on these matters sometimes run high," and offers an alternative practice, which is what Ruy is noting. This alternative practice, however, is noted as being less common. There are some assorted interesting exceptions (Words where the singular looks like a plural, and the plural is the same, are always formed simly by adding an apostrophe), and one policy I object to (Company names that include a punctuation mark, which I think should be reduced to their non-logo names), but for the most part, James is correct. Snowspinner 19:50, Jul 1, 2004 (UTC)

See also Possessive Forms for some discussion of various rules and The Apostrophe. See Possessive forms for the opposite of what Strunk wants. People just don't agree, in part because dialects and idiolects differ on when or whether an s is pronounced in such cases (and may not follow any easily derived rules with obvious consistancy). This should probably be considered part of allowable spelling differences in Wikipedia unless consensus on one style can be reached. The Wikipedia entry Apostrophe notes both styles and makes no recommendation. jallan 20:43, 1 Jul 2004 (UTC)

• The Elements of Style: Form the possessive singular of nouns by adding 's. Follow this rule whatever the final consonant, except for ancient names ("Jesus'") and forms such as "for righteousness' sake". Pronomimal possesives ("hers") have no apostrophe.

Even in Jesus's case I would form the possessive, to avoid confusion with the hypothetical singular "Jesu". "For goodness's sake!" [[User:Poccil|Peter O. (Talk)]] 00:16, Jul 8, 2004 (UTC)

• A Pocket Style Manuel: Add -'s if the noun does not end in -s or if the noun is singular and ends in -s. Exception: ackward pronunciation ("Sophocles'"). Add -' if the noun is plural and ends in -s.

Awkward prononciation? But you'd still have to say that "Soff-o-clease-ez", no? I'd imagine the reason you don't add the 's to Sophocles is the ancient names clause listed above. Though Chicago cites Elements of Style, but does not carry over that exception, so who knows. /sigh. We should really have a style committee for this. Snowspinner 21:15, Jul 1, 2004 (UTC)

Singular "sophocle"? [[User:Poccil|Peter O. (Talk)]] 00:16, Jul 8, 2004 (UTC)

In may own dialect I would say Sophocleez works not Sophocleezez works. The second sounds wrong to me. I would also, I think, generally say Charlz house rather than Charlzez house. I say "I think" because it is hard to be sure what one actually says as opposed to what one thinks one should actually say. Charles' house was also the way I was originally taught. That doesn't mean I'm right. Others speak differently and were taught differently. But obviously usage varies in pronunciation as well as spelling. Under current rules one should probably leave possessives alone if they follow either Strunk's rules or the Fowler rules (and perhaps sometimes even when they don't?) jallan 15:08, 2 Jul 2004 (UTC)

Well, I'd say that some people were taught wrong. The question is just which people they are. :) Snowspinner 16:20, Jul 2, 2004 (UTC)

Punctuation as punctuation

When words are written about as words, they are italicised. But what is the convention when punctuation is written about as punctuation? Should the punctuation marks be italicised in the same way? I notice that there are inconsistancies within the articles about punctuation.

For example, should one write, "The & sign," or write, "The & sign"? Danikolt (Talk) 22:03, 19 Nov 2004 (UTC)

How about something like: "The ampersand (&) is..." —Mike 23:28, Nov 19, 2004 (UTC)

In other words, a punctuation symbol should never be used directly, but referred to by name instead. The symbol should only be used the first time that it is referred to, in which case it should be enclosed in parentheses. Danikolt (Talk) 14:54, 22 Nov 2004 (UTC)

That's a good idea. Maurreen 16:03, 22 Nov 2004 (UTC)

Hyphens

Aside from the discussion about different kinds of dashes, is there advice, here or on one of the other pages, about when to use a hyphen in spelling a word? For example, I usually use a hyphen if the prefix re is attached to a word beginning with a vowel, so as not to create a false dipthong that might momentarily confuse the reader: re-elect, re-align, etc. I bring this up because I've seen an edit that, among other changes, deleted such hyphens, changing previous forms to reelected and reestablish. (Hyphens are also appropriate when the prefix could otherwise be read as creating a different word, e.g., to sign again is re-sign because resign means something else.) JamesMLane 19:42, 30 Nov 2004 (UTC)

Yes. But I forget where it is. I have most definitely read a sensible set of guidelines here on Wikipedia on its usage though. zoney ♣ talk 20:17, 30 Nov 2004 (UTC)

Since we don't know where it is, how about we add it? Here's the rule from the AP style guide:

"Except for 'cooperate' and 'coordinate', use a hypen if the prefix ends in a vowel and the word that follows begins with the same vowel."

Of course, if anyone can word this better, or would like to use a different style guide as a source, that is fine with me. Maurreen 07:22, 1 Dec 2004 (UTC)

Just to clarify, that's not the entire entry. Maurreen 05:58, 2 Dec 2004 (UTC)

I would also hyphenate re-align and other such words, though not covered by the rule you suggest. A reader seeing realign has seen enough words using "real" as a beginning that there'd be a momentary hitch while the reader sorts out that this isn't the familia ea combination and the familiar "real" beginning, but something else. The hyphen averts that. By the way, does the AP guide also address instances like re-sign? JamesMLane 07:34, 1 Dec 2004 (UTC)

It's one of the examples the AP Stylebook gives for the handling of the re prefix. "For many other words, the sense is the governing factor: ... resign (quit) re-sign (sign again)". Our style guide should probably state this position as well, as there's great potential for confusion otherwise; I once heard of an instance in which someone forwarded an email from her boss, and told him "I resent your email." Factitious 08:14, Dec 1, 2004 (UTC)

Good points, and some humor, too, which this page needs. :) Maurreen 08:27, 1 Dec 2004 (UTC)

I think I may have been only be thinking of what I had read at hyphen. If there are guidelines on hyphen usage already, or we are drafting such, we should probably ensure that article matches our practice. zoney ♣ talk 23:54, 1 Dec 2004 (UTC)

It's interesting that the article on hyphen misuses a hyphen, in the phrase "slightly-tilted slash". I'll correct that and add the point that a compound phrase in which an adverb modifies an adjective, with the phrase then modifying a noun, generally doesn't need a hyphen because it's unambiguous. (In this example, "slightly" can't modify "slash".) Perhaps we should include this in the MoS. Even if we do, people will still write "wholly-owned subsidiary", but we can at least try to stop them. JamesMLane 00:39, 2 Dec 2004 (UTC)

If the word is listed in a standard dictionary, then no hyphen should be used. Lots of dictionaries list "realign" and "reelect" as words, and therefore no hyphen should be used. If a word with "re" in front of it is not a standard form but rather a neologism, then use the hyphen ("re-") until the word is common enough to become a standard form. —Lowellian (talk)[[]] 21:46, Dec 3, 2004 (UTC)

"Standard dictionary" is a tall order! But in any case, I feel hyphens should be used with the "re" prefixes. Pairs of vowel letters such as ee and ea are single vowel sounds in English, so omitting the hyphen from re-align and re-elect indeed interrupts the flow of the language being read - the reader has to mentally divide the two vowel letters into two separate vowel instances. However, both forms are in common use, so once again I suggest we do not attempt to offer advice on this (i.e. force a rule), save perhaps mentioning the issue. zoney ♣ talk 00:03, 6 Dec 2004 (UTC)

For the reason stated by Zoney, I would hyphenate re-align but not reopen. The difference is that "eo" isn't used as a single vowel sound. Still, if the "rule" that's settled on is that re-align and realign are both OK, then the MoS should at least state that, so people don't waste time changing one to the other. JamesMLane 00:38, 6 Dec 2004 (UTC)

But User:Factitious's comments about the differences between "resent" and "re-sent" and similar words have merit, so hyphens should be used in those cases to make clear what is meant. —Lowellian (talk)[[]] 21:52, Dec 3, 2004 (UTC)

• My dictionary says "re-elect or reelect". And it also gives 'realign' but not 're-align'; I think the latter form is unnecessary because there is no ambiguity as there might be with a word like 'resent'. For separating the prefix and root of words, the dictionary gives these examples:
  1. prefix + proper noun or adjective (anti-Nazi, pro-Nazi)
  2. some prefixes ending in a vowel + root beginning with a vowel (re-election, co-author)
  3. stressed prefix + root word if absence of hyphen could cause misunderstanding of meanings (re-form/reform, re-cover/recover, re-creation/recreation)

Perhaps examples like these should be included and otherwise leave well-enough alone. We shouldn't have to construct a list of approved words. —Mike 01:45, Dec 6, 2004 (UTC)

This conversation perhaps ought to be mentioned on the talk page for the style guide page on dashes.

Also, I don't feel strongly about this, but on further thought, I wonder if there is a real need for this to be added to the style guide at all. Maurreen 05:56, 7 Dec 2004 (UTC)

I don't have my CMOS handy, but I'm pretty sure it says not to hyphenate prefixes at all unless (a) the second part is capitalized (e.g., anti-Nazi but antidisestablishmentarianism) or (b) omitting the hyphen would change the sense of the word (e.g., re-sent but realign). I believe British usage tends toward more hyphenation, though. I note that, from my perspective, the AP style guide is not a reliable guide to good usage; it advocates many usages that are unacceptable in formal English (and will get a writer in trouble, for example, with an academic editor), in part because of its orientation toward wire services with primitive teletype equipment (e.g., IIRC it advocates never using italics and omitting all accent marks and diacriticals on non-English names). —Tkinias 20:28, 7 Dec 2004 (UTC)

Possessives of words ending in 's'

There is currently a bit of controversy over whether Wikipedia writers should follow AP conventions or Strunk and White's conventions for dealing with possessives of words that end in 's'. For example, is it "Texas' Law" or "Texas's Law"? It would be nice if the Wikipedia Manual of Style could provide some guidance on this. Some articles have been reverted back and forth many times due to this controversy.

• AP Style Guidelines: SINGULAR PROPER NAMES ENDING IN S: Use only an apostrophe: Achilles’ heel, Agnes’ book, Ceres’ rites, Descartes’ theories, Dickens’ novels, Euripides’ dramas, Hercules’ labors, Jesus’ life, Jules’ seat, Kansas’ schools, Moses’ law, Socrates’ life, Tennessee Williams’ plays, Xerxes’ armies.
• Strunk and White's Elements of Style (used by US Government and others): Form the possessive singular of nouns with 's. Follow this rule whatever the final consonant. Thus write, Charles's friend, Burns's poems, the witch's malice.

Using either "s's" or "s'" is standard English - there's no reason for us to prefer one form over another. I don't see why there should be a controversy - unless those who prefer one form over another seek to impose their views on those who prefer the other form. Use whatever seems sensible at the time. jguk 23:51, 14 Jan 2005 (UTC)

I'm not sure that AP style is always the best. The AP guide also says don't use a comma before the 'and' in a series while the Elements of Style and Oxford's guide do. —Mike 00:25, Jan 15, 2005 (UTC)

Be careful on the Oxford comma. Its use (except where it is necessary to avoid ambiguity) is generally considered optional - with some style guides recommending its usage and others recommending using it only where necessary to avoid ambiguity, jguk 00:49, 15 Jan 2005 (UTC)

Since AP is a style guide for newspapers, where space is at a premium, it often chooses rules which result in fewer characters. It's not necessarily a good guide to use for books, or for Wikipedia, where space is less of an issue. - Nunh-huh 00:58, 15 Jan 2005 (UTC)

I would have thought that for Wikipedia space is also a premium: it has to be read on phones etc, so the shorter words are the better. (True, vertical space is not a constraint, just horizontal.) So I think it is better for authors who are concerned to err on the side of s' rather than s's (unless there is some clear disambiguating reason...but even then, I am not sure it is friendly to readers to rely on their understanding of possessive apostrophes to figure out what a sentence means.) Rick Jelliffe (talk) 03:43, 1 May 2023 (UTC)

If both are acceptable, it would be nice if the Wikipedia Manual of Style stated that both are acceptable, as there are definitely those out there seeking to impose their views on those who prefer the other form regardless of what is sensible. Kaldari 00:52, 15 Jan 2005 (UTC)

Style guides don't determine "correctness": they represent sometimes arbitrary choices between correct usages to obtain unifomity of style. This is probably unattainable at Wikipedia, where there's no authority to make such arbitrary choices. - Nunh-huh 00:58, 15 Jan 2005 (UTC)

If that's true then why does WIkipedia have a style guide at all? You presumption that it is only possible for "authorities" to make decisions about style seems a bit rash to me. Surely we can reach a reasonable decision that will help those seeking clarification, even if the decision is only to declare both styles acceptable. Otherwise this argument will continue to be played out over and over again across many separate articles with no resolution. Let's hash it out here so that people will have something to refer to at least. Kaldari 01:08, 15 Jan 2005 (UTC)

Standards fall into three categories: (1) Things where the clearly is a "right" and "wrong" and where it is important that things be "right" (e.g. spelling of words where there is only one standard spelling). (2) Things where there is legitimate disagreement about a consequential matter, and where we probably need to tolerate diversity (e.g. U.S. vs. UK English). (3) Things that are so trivial that almost any sane standard is better than no standard, because uniformity is more important than any particular resolution of the matter. This is an example of the last. -- Jmabel | Talk 01:29, Jan 15, 2005 (UTC)

I agree completely - but I fear that here are at least some users who will refuse to recognize class (3)<g>. - Nunh-huh 02:19, 15 Jan 2005 (UTC)

BTW, it looks like this issue was already discussed here back in July, but nothing came of it: Talk Archive 6. Kaldari 02:20, 15 Jan 2005 (UTC)

It looks like it was already mentioned in the previous discussion, but let me add what my personal favorite style guide has to say about it:

• The Chicago Manual of Style (15th edition): "The possessive of most singular nouns is formed by adding an s, and the possessive of plural nouns (except for a few irregular plurals that do not end in s) by adding an apostrophe only...The general rule covers most proper nouns, including names ending in s, x, or z, in both their singular and plural forms, as well as letters and numbers" (emphasis theirs). They give examples such as "Kansas's legislature", "Burns's poems", "Marx's theories", and so on. They also mention the alternative style, for those that do not like this method.

Aside from Chicago's support, there are other reasons I think this is appropriate. Why should "Texas's law" be any different from "Nebraska's law"? They are both pronounced equivalently. Texas is not a plural, and there is no need to use plural possessive forms with it. Nor would just adding an apostrophe avoid ambuguity; rather, it can actually further it (is Roberts' work the work of one Roberts [Julia Roberts] or the work of multiple Roberts?). Using just an apostrophe when words end in s, regardless of why they end in s, seems a bit artificial to me. — Knowledge Seeker দ (talk) 18:52, 15 Jan 2005 (UTC)

Most people pronounce "Texas' Law" differently than "Texas's Law". In fact, it is considered orthodox practice to pronounce them differently [1]. I suspect this is why the exception for words that end in s was created in the first place -- to eliminate awkward pronunciations. Take for example, "goodness' sake". That phrase is almost universally pronounced without the extra s sound regardless of whether the extra s is written. Otherwise it would sound quite awkward. "Olbers' paradox" is certainly easier to pronounce than "Olbers's paradox". The former sounds much more natural, thus the tradition of spelling it without the extra s. Whatever standard we decide on, I think we should make consideration for established exceptions, i.e. phrases that have always been spelled a certain way by convention regardless of standards. Kaldari 19:42, 15 Jan 2005 (UTC)

Fowler's Modern English Usage (a standard for British English) suggests dropping the post-apostriphal s if it is unvoiced. This still leaves something of a chicken and egg problem -- is it spelled because of how it's pronounced, or is it pronounced because of how it's spelled? Kaldari 19:57, 15 Jan 2005 (UTC)

I don't think it is a problem. The writer would spell it the way he pronounces it, and the reader would pronounce it the way the writer spelled it. Simple! —Mike 20:12, Jan 15, 2005 (UTC)

I started that earlier discussion (the one now in Talk Archive 6). The Strunk and White style still seems better to me. Olbers's paradox is preferable because hearing Olbers' paradox (pronounced "Olbers" instead of "Olberses") will lead some people to think that it's Olber's paradox. Nevertheless, that particular example, like for goodness' sake, might be a candidate for an exception, something like: "Form the possessive singular of nouns with 's. Follow this rule whatever the final consonant. Exception: Omit the s after the apostrophe if a particular possessive has become generally known without the final s." One argument advanced at Wikipedia:Requested moves#Olbers's paradox → Olbers' paradox is that this particular phrase, which dates back to Olbers's work in 1823, is more often written as Olbers' paradox. I admit that making such an exception would lead to sentences like "Olbers's students were initially confused by his explanation of Olbers' paradox." JamesMLane 22:30, 15 Jan 2005 (UTC)

It looks like all the main style guides, with the exception of the AP's, recommend using the s. Also I should mention that I did not quote Chicago's entire recommendation; in particular, they mention, "To avoid an awkward appearance, an apostrophe without an s may be used for the possessive of singular words and names ending in an unpronounced s. Opt for this practice only if you are comfortable with it and are certain that the s is indeed unpronounced." Examples: "Descartes' three dreams", "the marquis' mother". Also, "For...sake expressions traditionally omit the s when the noun ends in an s or an s sound." Examples: "for righteousness' sake", "for goodness' sake". James, your proposal sounds quite reasonable to me. — Knowledge Seeker দ (talk) 23:45, 15 Jan 2005 (UTC)

I wouldn't want to be prescriptive on this point. Besides, any instructions would largely be ignored by those who prefer the opposite approach. Burchfield in Fowler's Modern English Usage recommends just using an apostrophe in classical names, eg Herodotus', Socrates', Themistocles', etc. Note also that the official names of various institutions/places adopt differing approaches - for instance, it's not too difficult to find some institutions starting with "St James's" and others with "St James'", jguk 08:14, 17 Jan 2005 (UTC)

How does this sound:
Possessives ending in s
Authoritative sources differ on how to handle possessive nouns that end with the letter s. Some say to add an apostrophe and an s at the end. Other say to just add an apostrophe. Still others say it depends on whether the word is a proper noun, the s is pronounced a certain way, or a variety of other conditions are met. Because there does not seem to be a widespread consensus on how to handle possessives ending in s, both usages are considered acceptable in Wikipedia. In general, whichever usage of a particular word or phrase is most common should be used. For example, Olbers' paradox is more commonly used than Olbers's paradox.
Kaldari 17:27, 17 Jan 2005 (UTC)

Too many "somes" - and I don't like the use of the word authoritative. Maybe we could lift something from The Times and adapt it, for example (the bit not in italics is my addition, and I have redacted a small bit) jguk 19:15, 17 Jan 2005 (UTC):

with proper names/nouns ending in s that are singular, follow the rule of writing what is voiced, eg, Keats's poetry, Sobers's batting, The Times's style (or Times style); and with names where the final "s" is soft, use the "s" apostrophe, eg, Rabelais' writings, Delors' presidency. Note that with Greek names of more than one syllable that end in "s", do not use the apostrophe "s", eg, Aristophanes' plays, Achilles' heel, Socrates' life, Archimedes' principle. Beware that some people voice "s" that others don't, and this will change how they write the words. Some write "Jesus'" others "Jesus's". Also beware of organisations that have variations as their house style, eg, St Thomas' Hospital, where we must respect their whim. Also, take care with apostrophes with plural nouns, eg, women's, not womens'; children's, not childrens'; people's, not peoples'. Use the apostrophe in expressions such as two years' time, several hours' delay etc. An apostrophe should be used to indicate the plural of single letters - p's and q's

How about this:
Possessives
To form the possessive of a singular noun that ends in s, the general rule is to add an apostrophe and an s, for example, Charles's book. Exceptions to this rule are as follows:

• When the final s of the noun is soft or unpronounced: Descartes' theories, Rabelais' writing
• When there is a long-established tradition of adding only an apostrophe to form the possessive: Achilles' heel, goodness' sake
• When the possessive is part of an organization's name and they choose to only use an apostrophe: St Thomas' Hospital

For plural nouns that do not end in s, add an apostrophe-s, for example, children's, not childrens'.
Kaldari 20:33, 17 Jan 2005 (UTC)

Nearly there, methinks. Three points:

1. Reword to say "the general rule is that where the s is pronounced separately, add an apostrophe and as s". Then the first bullet point of exceptions to the rule becomes a further example of the general rule.

2. "Proper name" would be better than "organisation" as "organisation" is too specific.

3. Sake tends to be treated differently. In Fowler's Modern English Usage Burchfield writes, "For appearances' sake, for Christ's sake, for God's sake, for Heaven's sake, for Pete's sake, for old times' sake illustrate the obligatory use of the possessive apostrpohe in such phrases, Practice varies widely in for conscience' sake and for goodness' sake, and the use of an apostrophe in them must be regarded as optional." Burchfield goes on to say that in American English sakes is sometimes used in place of sake, jguk 22:12, 17 Jan 2005 (UTC)

1. Are you talking about the s of the original noun or the possessive s? If you're talking about the possissive s, I don't like instructing people to rely on whether the extra s is pronounced or not, as whether or not the extra s is pronounced often depends on how the possessive is spelled [2]. Thus we would be sending the writer in a circle: how it's written depends on how it's pronounced and how it's pronounced depends on how it's written. That's too confusing. If you're talking about the s of the original noun, then your wording is just incorporating the initial exception into the rule itself, and I'm not sure why that would be any better than listing it as an explicit exception and keeping the rule itself simplified.

2. Agreed.

3. That seems to fall into my 2nd exception. Ideally, I'd like to refrain from starting a long list of specific exceptions like greek names, something's sake, etc. and just create a general exception for traditional spellings. Kaldari 23:05, 17 Jan 2005 (UTC)

How about a more concise way, such as this:

"Possessives of words ending in 's' may be formed with or without an additional 's'." Maurreen 05:07, 18 Jan 2005 (UTC)

I like the conciseness, but I do think there are definite cases where writers should use one or the other and it would be nice if we could provide them some guidance on that. Kaldari 15:33, 18 Jan 2005 (UTC)

That's so concise it is useless. You might as well just say, "Possessives: no standard". Or just don't say anything at all. —Mike 01:00, Jan 19, 2005 (UTC)

I actually think it's useful in some cases to point out that we have no standard. This provides an authoritative resource to cite if there is a dispute. (I.e. "no, we don't need to standardize all references to plural possessives; Wikipedia permits either usage".) -Aranel ("Sarah") 01:31, 19 Jan 2005 (UTC)

If we are to explicitly state we have no preference, we need to be more explicit than Maurreen. Perhaps something along the lines of, "Where, a standard form of English permits possessives of words ending in 's' to be formed with or without an additional 's', we have no preference between those styles", jguk 01:44, 19 Jan 2005 (UTC)

OK, how does this sound:
Possessives
Opinions differ on how to form the possessive of singular nouns that end with the letter s. Some sources say to add an apostrophe and an s at the end. Others say to just add an apostrophe. Because there does not seem to be a widespread consensus on how to handle possessives of this form, both usages are considered acceptable in Wikipedia. In general, whichever usage of a particular word or phrase is most common should be used. For example, Achilles' heel is more commonly used than Achilles's heel.
For plural nouns that do not end in s, add an apostrophe and an s to form the possessive, for example, children's, not childrens'.
Kaldari 03:19, 23 Jan 2005 (UTC)

How about getting to the point more quickly, like this:

"Possessives of words ending in 's' may be formed with or without an additional 's'." Either is generally acceptable within Wikipedia. But if either form is much more common for a particular word or phrase, follow that form, such as with 'Achilles' heel'." Maurreen 22:47, 23 Jan 2005 (UTC)

I added your suggested guideline to the Usage and Spelling section. Kaldari 07:57, 26 Jan 2005 (UTC)

I think there is a general law of (English) orthography, that the more commonly used some word is, the more likely it is to be contracted. So we don't have apostrophes in (official) place names or railway stations, because they are used so much it is inefficient to have them. And by a similar action, s's is contracted to s' in names that are commonly used, such as the Greek classical authors and St Thomas' hospital. So, if you accept that, I think it indicates that if there is, say, an article about someone whose name ends in s, then the s' form should be gently favoured practice anyway.) So, say the article on Erasmus had something about his socks, I think Erasmus' socks would be best, because 1.no ambiguity results, 2. it does not draw attention to itself, 3. the initial s in socks makes too many esses, 4. Erasmus is a Latinity therefore should be treated as other classical names, 5. Erasmus is the subject of the article 6. pronunciation is no guide: Erasmusocks or Erasmus socks or Erasmus s socks?)