Vātsyāyana is the name of a Hindu philosopher in the Vedic tradition who is believed to have lived around 3rd century CE in India. His name appears as the author of the Kama Sutra and of Nyāya Sutra Bhāshya, the first commentary on Gotama's Nyāya Sutras.
Hardly anything is known about him, although it is believed that his disciples went on his instructions, on the request of the Hindu Kings in the Himalayan range to influence the hill tribals to give up the pagan cult of sacrifices. He is said to have created the legend of Tara among the hill tribes as a tantric goddess. Later as the worship spread to the east Garo hills,the goddess manifest of a 'yoni' goddess Kamakhya was created. His interest in human sexual behavior as a medium of attaining spirituality was recorded in his treatise Kama Sutra.
At the close of the Kama Sutra this is what he writes about himself:
"After reading and considering the works of Babhravya and other ancient authors, and thinking over the meaning of the rules given by them, this treatise was composed, according to the precepts of the Holy Writ, for the benefit of the world, by Vatsyayana, while leading the life of a religious student at Benares, and wholly engaged in the contemplation of the Deity. This work is not to be used merely as an instrument for satisfying our desires. A person acquainted with the true principles of this science, who preserves his Dharma (virtue or religious merit), his Artha (worldly wealth) and his Kama (pleasure or sensual gratification), and who has regard to the customs of the people, is sure to obtain the mastery over his senses. In short, an intelligent and knowing person attending to Dharma and Artha and also to Kama, without becoming the slave of his passions, will obtain success in everything that he may do."