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The Yoga Sutras are a composite of various traditions. The levels of samādhi taught in the text resemble the Buddhist jhanas. According to Feuerstein, the Yoga Sutras are a condensation of two different traditions, namely "eight limb yoga" (ashtanga yoga) and action yoga (Kriya yoga).

Patanjali begins his treatise by stating the purpose of his book in the first sutra, followed by defining the word "yoga" in his second sutra of Book 1:

योग: चित्त-वृत्ति निरोध:
yogaś citta-vṛtti-nirodhaḥ

— Yoga Sutras 1.2

This terse definition hinges on the meaning of three Sanskrit terms. I. K. Taimni translates it as "Yoga is the inhibition (nirodhaḥ) of the modifications (vṛtti) of the mind (citta)". Swami Vivekananda translates the sutra as "Yoga is restraining the mind-stuff (Citta) from taking various forms (Vrittis).

The eight limbs described by Patanjali are as follows:

  • Yama
  • Nyama
  • Asana
  • Pranayama
  • Prathyahara
  • Dharana
  • Dhyana
  • Samadhi


Trying to approach Yoga and meditation without developing strong qualities like Humility, Tolerance, Non Violence, Love, and morality, will only result in a waste of time.

  1. Yama

Yamas are ethical rules in Hinduism and can be thought of as moral imperatives. The five yamas listed by Patañjali in Yogasūtra 2.30 are:

  1. Ahiṃsā (अहिंसा): Nonviolence, non-harming other living beings
  2. Satya (सत्य): truthfulness, non-falsehood
  3. Asteya (अस्तेय): non-stealing
  4. Brahmacārya (ब्रह्मचर्य): chastity, marital fidelity or sexual restraint
  5. Aparigraha (अपरिग्रहः): non-avarice, non-possessiveness

Patanjali, in Book 2, states how and why each of the above self restraints help in the personal growth of an individual. For example, in verse II.35, Patanjali states that the virtue of nonviolence and non-injury to others (Ahimsa) leads to the abandonment of enmity, a state that leads the yogi to the perfection of inner and outer amity with everyone, everything.

  1. Niyama

The second component of Patanjali's Yoga path is called niyama, which includes virtuous habits, behaviors and observances (the "dos"). Sadhana Pada Verse 32 lists the niyamas as:

  1. Śauca: purity, clearness of mind, speech and body
  2. Santoṣa: contentment, acceptance of others, acceptance of one's circumstances as they are in order to get past or change them, optimism for self
  3. Tapas: persistence, perseverance, austerity
  4. Svādhyāya: study of Vedas (see Sabda in epistemology section), study of self, self-reflection, introspection of self's thoughts, speeches and actions
  5. Īśvarapraṇidhāna: contemplation of the Ishvara (God/Supreme Being, Brahman, True Self, Unchanging Reality)
  6. As with the Yamas, Patanjali explains how and why each of the above Niyamas help in the personal growth of an individual. For example, in verse II.42, Patanjali states that the virtue of contentment and acceptance of others as they are (Santoṣa) leads to the state where inner sources of joy matter most, and the craving for external sources of pleasure ceases.
  1. Āsana

Patanjali begins discussion of Āsana (posture) by defining it in verse 46 of Book 2, as follows,

Translation 1: An asana is what is steady and pleasant.
Translation 2: Motionless and Agreeable form (of staying) is Asana (yoga posture).

— Yoga Sutras II.46

Asana is thus a posture that one can hold for a period of time, staying relaxed, steady, comfortable and motionless. Patanjali does not list any specific asana, except the terse suggestion, "posture one can hold with comfort and motionlessness". Āraṇya translates verse II.47 of Yoga sutra as, "asanas are perfected over time by relaxation of effort with meditation on the infinite"; this combination and practice stops the quivering of body. The posture that causes pain or restlessness is not a yogic posture. Other secondary texts studying Patanjali's sutra state that one requirement of correct posture is to keep breast, neck and head erect (proper spinal posture).

Later yoga school scholars developed, described and commented on numerous postures. Vyasa, for example, in his Bhasya (commentary) on Patanjali's treatise suggests twelve: Padmasana (lotus), Veerasana (heroic), Bhadrasana (decent), Svastikasana (like the mystical sign), Dandasana (staff), Sopasrayasana (supported), Paryankasana (bedstead), Krauncha-nishadasana (seated heron), Hastanishadasana (seated elephant), Ushtranishadasana (seated camel), Samasansthanasana (evenly balanced) and Sthirasukhasana (any motionless posture that is in accordance with one's pleasure)

The Hatha Yoga Pradipika describes the technique of 84 asanas, stating four of these as most important: Padmasana (lotus), Bhadrasana (decent), Sinhasana (lion), and Siddhasana (accomplished). The Gheranda Samhita discussed 32 asanas, while Svatmarama describes 15 asanas.

  1. Prānāyāma

Prāṇāyāma is made out of two Sanskrit words prāṇa (प्राण, breath) and āyāma (आयाम, restraining, extending, stretching).

After a desired posture has been achieved, verses II.49 through II.51 recommend the next limb of yoga, prāṇāyāma, which is the practice of consciously regulating breath (inhalation and exhalation). This is done in several ways, inhaling and then suspending exhalation for a period, exhaling and then suspending inhalation for a period, slowing the inhalation and exhalation, consciously changing the time/length of breath (deep, short breathing).

  1. Pratyāhāra

Pratyāhāra is a combination of two Sanskrit words prati- (the prefix प्रति-, "towards") and āhāra (आहार, "bring near, fetch")

Pratyahara is fetching and bringing near one's awareness and one's thoughts to within. It is a process of withdrawing one's thoughts from external objects, things, person, situation. It is turning one's attention to one's true Self, one's inner world, experiencing and examining self. It is a step of self extraction and abstraction. Pratyahara is not consciously closing one's eyes to the sensory world, it is consciously closing one's mind processes to the sensory world. Pratyahara empowers one to stop being controlled by the external world, fetch one's attention to seek self-knowledge and experience the freedom innate in one's inner world.

Pratyahara marks the transition of yoga experience from first four limbs that perfect external forms to last three limbs that perfect inner state, from outside to inside, from outer sphere of body to inner sphere of spirit.

  1. Dhāranā

Dharana (Sanskrit: धारणा) means concentration, introspective focus and one-pointedness of mind. The root of word is dhṛ (धृ), which has a meaning of "to hold, maintain, keep".

Dharana as the sixth limb of yoga, is holding one's mind onto a particular inner state, subject or topic of one's mind. The mind (not sensory organ) is fixed on a mantra, or one's breath/navel/tip of tongue/any place, or an object one wants to observe, or a concept/idea in one's mind. Fixing the mind means one-pointed focus, without drifting of mind, and without jumping from one topic to another.

  1. Dhyāna

Dhyana (Sanskrit: ध्यान) literally means "contemplation, reflection" .

Dhyana is contemplating, reflecting on whatever Dharana has focused on for a long time. If the concentration was on one object, Dhyana is non-judgmental, non-presumptuous observation of that object.If the focus was on a concept/idea, Dhyana is contemplating that concept/idea in all its aspects, forms and consequences. Dhyana is uninterrupted train of thought, current of cognition, flow of awareness.

Dhyana is integrally related to Dharana, one leads to other. Dharana is a state of mind, Dhyana the process of mind. Dhyana is distinct from Dharana in that the meditator becomes actively engaged with its focus. Patanjali defines contemplation (Dhyana) as the mind process, where the mind is fixed on something, and then there is "a course of uniform modification of knowledge". Adi Shankara, in his commentary on Yoga Sutras, distinguishes Dhyana from Dharana, by explaining Dhyana as the yoga state when there is only the "stream of continuous thought about the object, uninterrupted by other thoughts of different kind for the same object"; Dharana, states Shankara, is focussed on one object, but aware of its many aspects and ideas about the same object. Shankara gives the example of a yogin in a state of dharana on morning sun may be aware of its brilliance, color and orbit; the yogin in dhyana state contemplates on sun's orbit alone for example, without being interrupted by its color, brilliance or other related ideas.

  1. Samādhi

Samadhi (Sanskrit: समाधि) literally means "putting together, joining, combining with, union, harmonious whole, trance".

Samadhi is oneness with the subject of meditation, shifting the contemplation to the source of the object, the one from which all originate, which is also one with the observer.There is no distinction, during the eighth limb of yoga, between the actor of meditation, the act of meditation and the subject of meditation. Samadhi is that spiritual state when one's mind is so absorbed in whatever it is contemplating on, that the mind loses the sense of its own identity. The thinker, the thought process and the thought fuse with the subject of thought. There is only oneness, samadhi. This doesn't necessary mean trance or becoming unconscious. The Gnani, the self-realized soul, who see everything as himself, is in Turiya, pure consciousness, a state similar to Samadhi, indescribable and beyond all definitions.

https://en.wikipedia.org/wiki/Yoga_Sutras_of_Patanjali#Eight_components_of_yoga