The doctrines of the Hindu trinity of Brahma, Vishnu and Siva, and that of the Platonic triad and Christian Holy Trinity are well known to inculcate the worship and meditation of the three persons in one, so that in adoring one of them, a man unknowingly worships all the three together. [Sidenote: 13. The Polytheistic yoga or _Sarva Devopásana_.] This consists of the adoration of a plurality of deities in the mythology by every Hindu, though every one has a special divinity of whom he is the votary for his particular meditation. The later upanishads have promulgated the worship of several forms of Vishnu and Siva (Web. I. Lit. p. 161); and the _Tantras_ have given the _dhyánas_ or forms of meditation of a vast member of deities in their various forms and images (Ibid. p. 236). [Sidenote: 14. The Atheistic or _Niríswara_ yoga.] The Atheistic yoga is found in the _niriswara_ or hylo-theistic system of Kapila, who transmitted his faith “in nothing” to the Buddhists and Jains, who having no God to adore, worship themselves, in sedate and silent meditation. (Monier Williams, Hindu Wisdom p. 97). [Sidenote: 15. The Theistic or _Ástikya yoga_.] The Theistic yoga system of Patanjala: otherwise called the _seswara_ yoga, was ingrafted on the old atheistic system of Sánkhya with a belief in the Iswara. It is this system to which the name yoga specially belongs. (Weber’s Ind. Lit. pp. 238 and 252). [Sidenote: 16. The Practical _Yoga Sádhana_.] “The yoga system,” says Weber, “developed itself in course of time in outward practices of penance and mortifications, whereby absorption in the Supreme Being was sought to be obtained. We discover its early traces in the Epics and specially in the Atharva upanishads.” (Ind. Lit. p. 239). The practical _yoga Sádhana_ is now practised by every devotee in the service of his respective divinity. [Sidenote: 17. The devotional or _Sannyása yoga_.] The devotional side of the yoga is noticed in the instance of Janaka in the Mahábhárata, and of Yájnavalkhya in the Brihadáranyaka in the practice of their devotions in domestic life. These examples may have given a powerful impetus to the yogis in the succeeding ages, to the practice of secluded yoga in ascetism and abandonment of the world, and its concerns called Sannyása as in the case of Chaitanya and others. [Sidenote: 18. The Speculative _Dhyána yoga_.] It had its rise in the first or earliest class of Upanishads, when the minds of the Rishis were employed in speculations about their future state and immortality, and about the nature and attributes of the Supreme Being. [Sidenote: 19. The Ceremonial or _Kriyá yoga_.]