Tantra

Life is difficult when the cow has no milk. (La vita è difficile quando la vacca è senza latte. - Proverb from Trentino

The proverb works with sheep too. Not every shepherd is served by hindering his cattle or sheep from begetting youngs and by that stop the milk from flowing after some time.

We speak of "the milk of human kindness." Human milk is a mark of having had sex. Now, there is tantra yoga too, including sex yoga. Kriya yoga may be called kundalini yoga, tantra yoga, or hatha-yoga. There are many forms of yoga, and many forms of tantra yoga, he also tells. So many forms intermingle.

To elaborate on that, in the twelfth chapter of The Deeper Dimensions of Yoga (2011), Georg Feuerstein discerns between forty types of Hindu yoga. Several of these yoge forms involves kundalini yoga, and tantra is kundalini-based too.

Georg Feuerstein and Larry Payne (2010) write:

In the West and in India, Tantra Yoga is often confused with "spiritualized" sex; although sexual rituals are used in some (so-called left-hand) schools of Tantra Yoga, they aren't a regular practice in the majority of (so-called right-hand) schools. . . .

Another common name for Tantra Yoga is Kundalini Yoga (pronounced koon-dah-lee-nee). . . . Tantra Yoga seeks to activate . . . the latent spiritual energy . . . Kundalini Yoga is also the name of a Hatha Yoga style. (Ib. 16)

This is to say that there are many forms of tantra yoga, and that tantra yoga not solely about sex. [See Satyananda Yoga]

Anyway, some may enjoy sex, life, success and wise yoga. Feuerstein (1990) explains that tantra (literally "loom") specifically refers a work in a genre in the tradition of Buddhism and Shaivism. There are many dialogues between God and the Goddess. The Tantras cover a wide range of subjects. There are also instructions about activating what is called kundalini-shakti, which is much of what Tantrism is about.

The origins of Tantrism are obscure, but Tantrism emerged as a distinct tradition within Hinduism, Buddhism, and Jainism in the early post-Christian era. Tantricism has a long history and great diversity, which makes it hard to generalize about it. Yet the pivot of most Tantric schools is the idea of somehow enlisting the help of shakti, the feminine principle the Goddess. This is expressed in many ways, including kundalini-yoga.

(Source, Feuerstein 1990, "tantra, tantricism")

Tantra or sex. If it works, fine. If not, "There is nothing more dreadful than a fool and a lunatic (Japanese proverb,). They may get many children, though. There is a knack to lots of things, including happy and fulfilling mating.

Kriya yoga is tantric, as shown in Satyananda Yoga.

The tantric tradition denotes teachings and practices found in the scriptures known as tantras or agamas.

The tantras are varied scriptures.

The agamas are scriptures that teach regulations of worship, deities, philosophical doctrines, meditation practices, attainment of desires and various sorts of yoga. Agamas speak of Kundalini Yoga as well.

Vajrayana, "the diamond way", denotes tantric Buddhism. Hindu and Buddhist yogas contain tantra teachings. They are varied. Here is one understanding among many; John Blofeld writes, "my Lama teachers summed up the general requirement for developing a Tantric attitude in three injunctions: "Recognize everything around you as Nirvana; hear all sounds as Mantra; see all beings as Buddhas." (Blofeld 2002:40)

• Nirvana may be understood as Joyful Essentiality. (cf. ibid.; Lie 2005:11-13: Nirvana is not an extinction of oneself. For example, Gautama Buddha lived and taught for forty years after he found Nirvana. Lie points out that the word nirvana has been frequently misunderstood. It is a happy realm to enter, a very desirable inner state of insight, happiness and peace. [Cf. Lie 1992:8]

  Other interpretations are found too, but the basic old meanings remain the same. (Lie 2005:11-13)

• Mantras are syllables, sets of syllables, or invocations used for meditation and rituals, as the case may be. The effects may become potent. (Blofeld 2002:40-41)
• A Buddha is awakened in Essence. Jonh Blofeld: "Seeing all beings as Buddhas is an injunction . . . based on the understanding that every being has within him Buddha-nature (Tathagata-garbha) . . . the undifferentiated non-substance (etc) (Op.cit 41)."

Tibetan Tantra

The Six Yogas of Naropa and the Six Yogas of Niguma . . . these lineages came through Naropa, although the latter was further developed and refined by Naropa's female disciple Niguma (cf. Harding 2010). Today Tibetan sects like the Karma Kagyu (see Thinley 1980) often use a blend of these two. . . .

The sixth yoga in the Naropa system, known as "forceful entry," . . . The Niguma system does not incorporate this yoga . . .

The transmission of the Six Yogas of Naropa was imported and translated into Tibetan by Marpa Lotsawa (Heruka 1982) . . . the transmission of the Six Yogas of Niguma (Mullin 1985) was imported and translated by Khyungpo Naljor (see Riggs 2001, 44-93) a generation later . . .

These [two] "Six Yogas" systems are fusions of various elements extracted from various Buddhist tantras.

(Mullin 2006, 85-87, passim)