On higher levels of initiation and practice of tantrism, such as pūrṇābhiṣeka, medhā-sāmrājya and practices of upper āmnāya, there are methods of contemplation of Ardhanārīśvara. Also, such ritual as pañca-tattva is not usually practiced before śāktābhiṣeka dīkṣā, and this is especially true for higher initiations and āmnāyas. Such titles as left-handed or right-handed tantra have both symbolic and quite practical values, for instance, pātra with wine is taken by the left hand when we offer it to the ”inner fire” into the mouth of Kuṇḍalinī. The left part of the body is Śakti and the right is Śiva. Some tantrikas say that kaula sādhana begins where such dualistic methods as Patañjali yoga are ended. But the same could be said about nāthas and kaulas: nātha sādhana begins where kaula sādhana ends. It has always been like that in India: the more recent endevour to continue something is more substantial than the previous one. That is why Gorakṣanātha is more honoured today than even Matsyendranātha, but this, of course, does not belittle the benefit and the authority of the latter. In the same way, for example, Vedanta – the completion of the Vedas, is not considered as something below the Vedas, but rather as its essence by either Vedantins or many other Hundu. Or, similarly, we couldn’t say that Vajrayana Buddhism is a simplification of Theravada, despite the fact that it had been developed later. Or, for instance, the fact that some cults of early female deities, like sapta and aṣṭa mātrikās have been transformed into such sophisticated cults as Trika, Kubjikā, Śrīvidyā and others, doesn’t make the latter less developed or less authoritative. And the most essential way was always the most secret, with a very careful selection of applicants for that kind of dedication and practice. The same could be said about nāthas. The phenomenon of svara-yoga is of tantric origin, but its basis is still yogic. In speaking of essence, by which we usually mean something that is closer to us as subjects, and also implying the involvement of the subjects in different degrees of the external process. That is why the practices with the body, breathing, with tracking how the breath is associated with the sun and the moon, how these two are related to the elements, tithis, grahas, nakṣatras and other aspects of both micro- and macrocosmos, are very great and subtle processes. But the most important thing is that they are all tied to the essence of it all, namely the yoga of the Sun and the Moon. In many books of both the medieval gurus of the Nāth Sampradāya and the present authors, we can very often find a description of the importance of svara-yoga and, of course, the practices of it. That can be called the basis of nātha-yoga, as its symbol is the Sun and the Moon, i.e. Śiva-Śakti saṃyukta.