"Death is lighter than a feather, duty heavier than a mountain": According to John Pickett, the quote is an excerpt taken directly from the First Precept of the Imperial Rescript to Soldiers and Sailors, written in 1883 during the Meiji Period of Japanese history. David Vogt adds that it was also a popular proverb among Japanese suicide troops during the late stages of combat of the Second World War.
Jearom: The greatest swordsman who ever lived, who suffered his only defeat at the hands of a farmer armed with a quarterstaff. Erin O'Toole suggests that RJ's inspiration for that was Miyamoto Musashi, the kensai (sword saint) of Japan. In the novel Musashi by Eiji Yokohawa, his bout with the farmer is prominently featured, though it is not known if such a duel ever really happened.
In an interesting cross-reference, Ho-Sheng Hsiao notes that Musashi wrote a book a few weeks before he died called Go Rin No Sho, or "A Book of Five Rings". It is divided into the Ground Book, The Water Book, The Fire Book, The Wind Book, and The Book of the Void.
Stones: The game of Stones is based on the Asian game Go.
Sword forms: It's research (books, not doing), and the forms come from Japanese sword fighting and some European fencing, before the advent of well-designed and well-made guns made swords obsolete. [Matthew Hunter at a signing, also mentioned by others]
Tony Ho believes that the sword forms "more closely resemble Chinese Wu Shu fighting forms than Japanese sword forms. The Budoken (Japanese sword fighting) makes use of "forms," but does not name these forms. Wu Shu fighting, be it weapon or weaponless, associates each movement with a poetic title such as: "Mountain Crushing Overhead," Old Ox Charging Forward," and even "Swallows Taking Flight," which is also a sword movement."
Tower of Ghenjei: There is a Japanese novel called The Tale of Genji. It is generally considered the first piece of work which qualifies as a novel, as the genre is defined today. Note the name's similarity to the Tower of Ghenjei in WOT. It was written by Lady Murasaki Shikibu in the early 10th century, during the Heian Period of Japanese history. [Jeff Han]
Yin-Yang symbol: The ancient sign of the Aes Sedai. Taoist tradition holds that Yin represents everything that is feminine, dark, withdrawn, receptive and passive, and of movement down and in; Yang represents the masculine, bright, forceful and expansive, and movement out and up. RJ's version inverts the colors of the genders, but the symbolism of opposite forces in balance carries across unmistakably in the saidar/saidin dynamic:
"[RJ] also spoke for quite some time on the splitting of the One Power into male and female halves, and on the disharmony produced when they don't work together.. this came across as one of the core elements in the origin of WOT. (re: Yin/Yang - leaving out the little dots in the symbol is an intentional representation of the lack of harmony between male/female Power in Randland)" [Emmet O'Brien, Dublin talk, 11/93].