, also known as Hayashi Shunsai (æ æÂ¥æÂÂ), was a Japanese Neo-Confucian philosopher and writer in the system of higher education maintained by the Tokugawa bakufu during the Edo period. He was a member of the Hayashi clan of Confucian scholars.
Following in the footsteps of his father, Hayashi Razan, Gahà  (formerly Harukatsu) would devote a lifetime to expressing and disseminating the official neo-Confucian doctrine of the Tokugawa shogunate. Like his distinguished father, Gahà Â's teaching and scholarly written work emphasized Neo-Confucianist virtues and order.
Gahà  became the unofficial rector of what would become EdoâÂÂs Confucian Academy, the Shà Âhei-kà  (afterwards known as the Yushima Seidà Â). This institution stood at the apex of the country-wide educational and training system which was created and maintained by the Tokugawa shogunate. Gahà Â's hereditary title was Daigaku-no-kami, which, in the context of the Tokugawa shogunate hierarchy, effectively translates as "head of the state university".
In the elevated context his father engendered, Gahà  worked on editing a chronicle of Japanese emperors compiled in conformance with his father's principles. Nihon à Âdai Ichiran grew into a seven-volume text which was completed in 1650. Gahà  himself was accepted as a noteworthy scholar in that period; but the potent Shà Âhei-kà  and Hayashi family links to the workâÂÂs circulation are part of the explanation for this work's 18th and 19th century popularity. Contemporary readers must have found some degree of usefulness in this summary drawn from historical records.
The narrative of Nihon à Âdai Ichiran stops around 1600, most likely in deference to the sensibilities of the Tokugawa regime. Gahà Â's text did not continue up through his present day; rather, he terminated the chronicles just before the last pre-Tokugawa ruler. Gahà  modestly observed that "in a book intended for the shogun's eyes, it is incumbent upon one to be circumspect." This book was published in the mid-17th century and it was reissued in 1803, "perhaps because it was a necessary reference work for officials."
Gahà  would become his father's successor as advisor to the shogun. He was the Tokugawa shogunate's chief scholar. After Razan's death, Gahà  finished work his father had begun, including a number of other works designed to help readers learn from Japan's history. In 1665, Gahà  published an anthology of historical poems (Honchà  Ichinin Isshu). In 1670, the Hayashi family's scholarly reputation was burnished when Gahà  published the 310 volumes of .
Together with his brother, Hayashi Dokkà Âsai (formerly Morikatsu), Gahà  compiled, edited and posthumously published selections from their father's body of writings:
Gahà Â's son, Hayashi Hà Âkà  (formerly Nobuatsu), would eventually inherit the position as head of the Shà Âhei-kà  or Yushima Seidà Â, as well as the honorific Daigaku-no kami; and his progeny would continue the Hayashi traditions.
In January 1858, it would be the hereditary Daigaku-no-kami descendant of Hayashi Razan and Hayashi Gahà  who would head the bakufu delegation which sought advice from the emperor in deciding how to deal with newly assertive foreign powers. This would have been the first time the Emperor's counsel was actively sought since the establishment of the Tokugawa shogunate. The most easily identified consequence of this transitional overture would be the increased numbers of messengers which were constantly streaming back and forth between Tokyo and Kyoto during the next decade. There is no small irony in the fact that this 19th-century scholar/bureaucrat would find himself at a crucial nexus of managing political changeâÂÂmoving arguably "by the book" through uncharted waters with well-settled theories as the only guide.