This full-on section relates to samadhi. Here are some extracts I selected from this second half of the sixth chapter:

From cosmic intelligence sprouts cosmic energy and consciousness, and from these devolves ego or the sense of self.  From the one root comes duality (which is the ability to separate), from duality comes vibration (which is the pulse of life beginning), from vibration comes invisible manifestation, and from the invisible comes the visible in all its glorious and horrendous diversity and multiplicity. This end product is what we take the world to be–our playground, our paradise, or our hell and our prison. If we misapprehend nature, take it at face value, through ignorance, then it is our prison.

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Yoga examines in order to know, like science, but it wants to know in order to penetrate, to integrate, and to reconstruct through practice and detachment the perfection of nature’s original intention. In other words, it wants to reach the root and cut out the intervening turbulence. It does not want to be hoodwinked by nature’s appearance, but to adhere to its original motivation.

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So many people approach spiritual growth as if it were a lottery. They hope that some new book or new method, some new insight or teacher will be the lottery ticket that allows them to experience enlightenment. Yoga says no, the knowledge and the effort are all within you. It is as simple and as difficult as learning to discipline our own minds and hearts, our bodies and breath.

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When we are in the suspension of breath in the deepest meditation – a spontaneous, as it were, God-willed retention – we enter the black hole, the vortex of nothingness, the void. Yet somehow we survive. The curtain of time, time that inexorably brings death, is parted. This is a state of nonbeing, but a living nonbeing. It is a present devoid of past or future. There is no self, no meditator, no longer even any breather. What comes out of that black hole, that nothingness? Information. What is the information? The truth. What is the truth? Samadhi.

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For the beginner, samadhi is an alluring subject. But there are reasons not to get fixated on it. The beginner can only conceive of samadhi as a glorification of the self he knows.

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It is said that the meaning of life becomes apparent only in the face of death. At this point in practice the ego dissolves, or rather it gives up its impersonation of the true self.

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In meditation, consciousness faces the soul itself. Samadhi is seeing soul face to face. It is not a passive state. It is a dynamic one in which the consciousness remains in a state of equilibria in all circumstances. The disturbances of the mind and emotions fade away, and we are able to see true reality.

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After significant effort, a yoga practitioner reaches a state where some are some asana poses are effortless. What we achieve here externally is achieved through samadhi internally. It is an effortless state, where one experiences the grace of the self. This is a state of great bliss and fulfilment.

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If anybody says, “I am teaching meditation,” then as a student of yoga I say, “It is rubbish,” because meditation cannot be taught it can only be experienced.

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Sabija means ‘with seed’. What this means is that although the experience of bliss is felt, the seeds of desire remain in the ego as future potential. Even after the experience of samadhi, these seeds can sprout again and cause a relapse. The ego has not been entirely purified by the fire of the experience. This particular point on the yogic journey, although so elevated, is one of danger as it can become a wasteland in which the practitioner gets stuck. This state is called manolaya, which means an alert, passive state of mind. But in this context, it implies a complacency with what has been achieved and a tendency to slacken efforts to complete the final step of the journey. The yogi cannot rest on his laurels but must press on to the higher states of samadhi in which even the seeds of desire are burnt out from the ego forever and can never sprout or trouble him again. This is known as nirbija samadhi (seedless) in which the feeling of bliss is not dependent at all, even on a vestigial eager. This is the bliss of the absolute void, of nonbeing transformed into the light of being.

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I can assure you that everyone seeks samadhi, and most of us seek shortcuts to get there.

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People seek somebody through drugs, alcohol, the danger of extreme sports, the romanticism of music, the beauty of nature, and the passion of sexuality. There are 1000 ways and they all involve the transcendence of the suffering ego in a blissful fusion with an entity much greater than ourselves.

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Change leads to disappointment if it is not sustained. Transformation is sustained change, and it is achieved through practice.

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Dreams of the divine union, however high their aspirations, contain an element of fantasy. They may not be sustainable. We must have spiritual aspiration not spiritual pretension.

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Yoga is solid. It is the path I know, the path I trod, the path I teach. Everyone desires relief from both the restrictions of personality and its impermanence. Everyone desires samadhi. From the dawn of his history, man has sought dangerous, shoddy shortcuts as well as noble ones. Called the hard, sustained progress of yoga a long cut if you will, but if it is a long cut, then so is the flight of an arrow.