Laghu yoga Vasistha is a book published by Theosophical Publishing House, Adyar, Chennai. This is an abridged version of the Yoga Vasistha, a part of Ramayana by sage Valmiki. The original version, Brihu Yoga Vasistha is said to contain 36,000 verses, and that abridged by Abhnandhana contains 6000 verses, therefore called Laghu-yoga-vasistha. This English version is penned by Shri K.Narayanaswamy ayyar. This edition contains about 500 pages. This contains many stories, purported to have been briefed to Sri Rama by sage Vasistha, the Guru of Ikshvagu clan. It begins with a briefing that when sage Viswamitra visited Ayodhya to request the services of Sri Rama to save his Yagna from Asuras. After obtaining the assent of Dhasaratha with some persuasion, Viswamitra comes to know of the despondency of SriRama, who was, despite all royal comforts, living a life of an ascetic without attachment to any worldly affairs. Upon hearing his position, Viswamitra requests Vasistha to initiate Rama to the Philosophy of advaita and make him learned in the yogas. Thus Vasistha starts to upraise Rama of the highest principles of Advaita Vedanta by illustrating with many stories of various Kings, sages and Devas. The philosophical doctrine is divided into six prakaranas viz., Vairgaya, Utpatti, Mumukshu, Sthithi, Upasanti and Niravana prakaranas. Not only the stories of the past and the present at the time of Ramayans, but also the stories of those who are yet to come during the Mahbharatha period, which happened after several thousand years of Ramayana are also briefed in this epic. This is purely vedantic philososophical, that at the end of every story, a philosophical fact is explained; and as such it took more than a month to complete the book of about 500 pages. If one has the patience and interest in philosophy, this book is a must read.
Yoga Vasistha probably evolved over time. The first work, was the original ancient work of Vasistha that is lost. This text was expanded into Moksopaya or Yogavasistha-Laghu between 6th to 10th. The Laghu (shorter) version was later (no later than 14th) expanded which resulted in the Yogavāsiṣṭha. https://www.goodreads.com/book/show/1...
The author of the shorter version, the Laghu-Yogavasistha, is generally considered to be Abhinanda of Kashmir, who has been variously dated to have lived in 9th- or 10th-century.