The Deaths in 2013 site lists under September 10th:

Ivan Sag, 63, American linguist, cancer

How many people are aware that Ivan is John http://www.behindthename.com/name/ivan:

Newer form of the old Slavic name Іѡаннъ (Ioannu), which was derived from Greek Ioannes (see JOHN). 

So what do the inner twin world mean by "sag"

sag (v.) 

late 14c., possibly from a Scandinavian source related to Old Norse sokkva "to sink," or from Middle Low German sacken "to settle, sink" (as dregs in wine), from denasalized derivative of Proto-Germanic base *senkwanan "to sink" (see sink (v.)). A general North Sea Germanic word (cf. Dutch zakken, Swedish sacka, Danish sakke). Of body parts from 1560s; of clothes from 1590s. Related: Sagged; sagging.

sag (n.) 

1580s, in nautical use, from sag (v.). From 1727 of landforms; 1861 of wires, cables, etc.

saga (n.) 

1709, an antiquarians' revival to describe the medieval prose narratives of Iceland and Norway, from Old Norse saga "saga, story," cognate with Old English sagu "a saying" (see saw (n.2)). Properly, a narrative composition of Iceland or Norway in the Middle Ages, or one that has their characteristics. Meaning "long, convoluted story" is from 1857.

sagacious (adj.) 

c.1600, from Latin sagacem (nominative sagax) "of quick perception;" see sagacity. Related: Sagaciously.

sagacity (n.) 

c.1500, from Middle French sagacité, from Latin sagacitatem (nominative sagacitas) "keenness of perception, quality of being acute," from sagax (genitive sagacis) "of quick perception, acute," related to sagus "prophetic," sagire "perceive keenly," from PIE root *sag- "to track down, trace, seek" (cf. Old English secan "to seek;" see seek). Also used 17c.-18c. of animals, meaning "acute sense of smell."

sagamore (n.) 

"king or chief among some Native American tribes," 1610s, sagamo, from Abenaki (Algonquian) zogemo "chief, ruler," from the same root as sachem.

sage (n.1) 

kind of herb (Salvia officinalis), early 14c., from Old French sauge (13c.), from Latin salvia, from salvus "healthy" (see safe (adj.)). So called for its healing or preserving qualities (it was used to keep teeth clean and relieve sore gums, and boiled in water to make a drink to alleviate arthritis). In English folklore, sage, like parsley, is said to grow best where the wife is dominant. In late Old English as salvie, directly from Latin. Cf. German Salbei, also from Latin.

sage (adj.) 

"wise," c.1300 (late 12c. as a surname), from Old French sage "wise, knowledgeable, learned; shrewd, skillful" (11c.), from Gallo-Romance *sabius, from Vulgar Latin *sapius, from Latin sapere "have a taste, have good taste, be wise," from PIE root *sap- "to taste" (see sap (n.1)). Meaning "characterized by wisdom" is from 1530s. Related:Sageness.

sage (n.2) 

"man of profound wisdom," mid-14c., from sage (adj.). Originally applied to the Seven Sages -- Thales, Solon, Periander, Cleobulus, Chilon, Bias, and Pittacus.

sagebrush (n.) 

1850, from sage (n.1), to which it has no biological affinity, + brush (n.2). Said to be so called for resemblance of its appearance or odor.

Sage-brush is very fair fuel, but as a vegetable it is a distinguished failure. Nothing can abide the taste of it but the jackass and his illegitimate child, the mule. ["Mark Twain," "Roughing It"]

sagely (adv.) 

c.1400, from sage (adj.) + -ly (2).

saggy (adj.) 

1848, from sag (n.) + -y (2). Related: Saggily; sagginess.

sagittal (adj.) 

"shaped like or resembling an arrow," 1540s, from Modern Latin sagittalis, from Latin sagitta "arrow" (see Sagittarius).

Sagittarius (n.) 

zodiac constellation, late Old English, from Latin, literally "archer," properly "pertaining to arrows," from sagitta "arrow," which probably is from a pre-Latin Mediterranean language. Meaning "person born under Sagittarius" (properly Sagittarian) is attested from 1940. It represents a centaur drawing a bow, but to modern observers unfamiliar with either it looks vaguely like a teapot.

sago (n.) 

"starch made of the piths of palms," 1570s, via Portuguese and Dutch from Malay sagu, the name of the palm tree from which it is obtained (attested in English in this sense from 1550s). Cf. French sagou, Spanish sagu, German Sago.