Sei Shōnagon (清少納言), (c. 966 -1017) was a Japanese author and a court lady who served the Empress Teishi (Sadako) around the year 1000 during the middle Heian period. She is best known as the author of The Pillow Book (枕草子 makura no sōshi).

Sei Shōnagon's actual given name is not known. It was the custom among aristocrats in those days to call a court lady (女房nyōbō) by a nickname taken from her clan name or a court office belonging either a close male relative. Sei (清) derives from the Kiyohara (清原) clan, while Shōnagon refers to a government post. It is unknown which of her relatives held the post of shōnagon. However, she was called "Shōnagon" ("minor counselor") at court. Her actual name has been a topic of debate among scholars, who generally favor Kiyohara Nagiko (清原 諾子) as a likely possibility.

Little is known about her life except what can be found in her writing. She was the daughter of Kiyohara no Motosuke, a scholar and well-known waka poet, who worked as a provincial official. Her grandfather Kiyohara no Fukayabu was also a waka poet. The family were middle-ranking courtiers and had financial difficulties, possibly because they were not granted a revenue-producing office.

Helena Tulve (born April 28, 1972 in Tartu) is an Estonian composer.

Born in Tartu, she studied composition at the Tallinn Secondary Music School under Alo Põldmäe and from 1989–1992 at the Estonian Academy of Music with Erkki-Sven Tüür, being the latter’s sole student of composition thus far. In 1994 Tulve graduated with the Premier Prix from Jacques Charpentier’s composition class at the Conservatoire Superieur de Paris. Between 1993 and 1996 she furthered her knowledge of Gregorian chant. She has also attended György Ligeti’s and Marco Stroppa’s summer courses.

Tulve belongs to the younger generation of Estonian composers who, in contrast to the neo-classicist tradition of rhythm-centeredness, create music which focuses on sound and sonority. Tulve’s works give a fair idea of the richness and variety of her cultural experience: the French school of spectral music, IRCAM’s experimentalism, Kaija Saariaho and Giacinto Scelsi, echoes of Gregorian chant and Eastern musics. Deriving from her refined sound processing, Tulve’s approach to form is “fluid” – more process based than architectonic.