Q: My question for you has to do with my son, Thales, who’s named after the ancient Greek philosopher. Is the plural possessive of his name Thales’ (like Achilles’) or Thales’s (like James’s)? Also, do you pronounce it with two syllables or three.
A: This is a complicated question, since Thales is a classical name being used by someone living now.
Ordinarily, as we’ve written on our blog, a name ending in “s” is made possessive with the addition of an apostrophe and a final “s,” as in “James’s sailboat.”
In the past, classical and biblical names were an exception. Those ending in “s” were customarily made possessive without the extra “s” (as in “Achilles’ armor” and “Jesus’ disciples”).
In modern usage, however, this custom is no longer universally followed, as we wrote in a posting last year.
Today, classical and biblical names ending in “s” are frequently made possessive just like other names—with the extra “s.” And they’re pronounced, as one would expect, with an extra syllable.
That’s the word from the Chicago Manual of Style (16th ed.). Although some other guides recommend skipping the final “s,” the Chicago Manual says “such usage disregards pronunciation and is therefore not recommended by Chicago.”
Among the examples in the Chicago Manual are “Jesus’s adherents,” “Jesus’s sake,” “Tacitus’s Histories,” “Euripides’s tragedies,” and “Xerxes’s armies.”
This would seem to indicate that the name Thales, which has two syllables (THAY-leez), would become possessive as Thales’s, pronounced with three syllables (THAY-leez-ez).
But there’s a fly in the ointment. Chicago says possessive forms of classical and biblical names that end in an “eez” sound (like Thales and Hercules) are generally NOT pronounced with an extra syllable, even when spelled with an extra “s.”
So if you followed the Chicago Manual guidelines, you’d end up writing the possessive as Thales’s but not pronouncing the extra syllable, which seems silly to us. If that extra syllable is indicated in the spelling, it ought to be pronounced, in our opinion.
At bottom, of course, this is an issue of style, not correctness. In the end, the choice is really up to you (and to your son!).
Here’s what we advise. First, decide how you want to SAY the possessive form of his name, since you’ll be pronouncing it more often than you write it.
If you prefer to say “THAY-leez sailboat,” then spell it Thales’. But if you prefer to say “THAY-leez-ez sailboat,” with the extra syllable, then write the possessive form as Thales’s.
That’s the best advice we can come up with. If anyone questions your choice, you can argue reasonably for either one.
After all, your son isn’t a classical figure—he’s simply named for one: Thales of Miletus, one of the Seven Sages of ancient Greece.
People are entitled to decide how their names are pronounced, as we noted in a blog item a few years ago. So why can’t Thales decide how the possessive of his name should sound?
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