Siddhasana

The Hatha Yoga Pradipika names four postures as the essential ones and then goes further, singling out siddhasana from among those four and calling it the chief. The text says that of the eighty four postures Shiva taught, this one should always be practised, that it purifies the channels of the subtle body, and that it opens the door of liberation. Those are Svatmarama's claims and the atlas records them as his.

The description is exact. One heel is pressed firmly against the perineum, the other foot is set above the genitals, the chin is drawn toward the chest and the gaze is held steady between the eyebrows. Every element of that has a function in the system: the heel maintains a pressure the corpus associates with the lowest of the inner locks, the chin position is the throat lock, and the fixed gaze belongs to the concentration practices of the later chapters.

Read alongside the rest of the book, siddhasana is not one option among fifteen. It is the posture the Pradipika's whole apparatus of breath restraint, locks and seals is designed to be performed in, and the reason the text can afford to be brief about the other fourteen. A practitioner who had only this entry would still have the seat the book assumes.

Siddha means accomplished, perfected, one who has arrived. In the medieval religious world the hatha texts come from, it is also a title: the siddhas were practitioners understood to have attained a perfected body and the powers that came with it, and they form the milieu in which alchemical, tantric and yogic technique were pursued together. David Gordon White's The Alchemical Body reconstructs that world in detail, and Geoffrey Samuel's Origins of Yoga and Tantra sets it inside the longer development of Indic religion.

Naming a posture after them therefore claims something. It is not the posture of a person who is comfortable sitting; it is the posture of the accomplished, the seat of those who got where the practice goes. The Pradipika reinforces the claim by placing it above the other three principal postures and by attaching to it the promise of liberation.

The same root produces siddhi, the powers the tradition holds a practitioner may acquire along the way, and the ambivalence about those powers runs through the literature: they are evidence of progress and a distraction from it. That tension is part of what the name carries. The atlas records the claim the text makes and the world the word comes from, and leaves the claim standing as the tradition's rather than restating it as a finding.