This section defines the true meaning of Yoga as Rāja Yoga, the science of understanding and mastering the mind, explaining that physical Yoga is only one aspect of the broader Yogic tradition. The foundational text of Rāja Yoga is the Yoga Sūtras of Patañjali, a collection of concise teachings, or sūtras ("threads"), an ancient work that systematized existing knowledge into four sections covering contemplation, practice, accomplishments, and absoluteness. The text introduces Satchidananda, a contemporary Yoga master whose “Integral Yoga,” a comprehensive approach that addresses the physical, emotional, mental, intellectual, and social aspects of an individual, is presented as synonymous with Rāja Yoga. After extensive training in India, Satchidananda brought the teachings to the West with a universal, interfaith message summarized as “Truth is One, Paths are Many.” (xiii) It is explained that this book is based on a compilation of Satchidananda’s informal lectures and experiential interpretations of the sūtras, making the ancient science accessible to modern students. The Introduction concludes with the practical advice that readers memorize sūtras that resonate with them to aid in their daily lives.

This chapter defines Yoga as the restraint of the modifications (vṛttis) of the mind. When these mental fluctuations are stilled, the Seer (the true Self, or Puruṣa) abides in its own nature; otherwise, it falsely identifies with the modifications. There are five types of modifications—right knowledge, misconception, verbal delusion, sleep, and memory—which can be either painful or painless. Restraining them is achieved through dedicated, long-term practice (abhyāsa) and non-attachment (vairāgya). An alternative path to this state is through devotion and surrender to Īśvara (the supreme Self), whose name is expressed as the sound “OM.” Patañjali lists several obstacles to this practice, such as disease and doubt, and offers various techniques to calm the mind and achieve one-pointedness, including cultivating specific attitudes toward others and controlled breathing. The culmination of this practice is samādhi, a state of deep contemplation where the mind unites with its object. The chapter details progressive stages of samādhi, a state of deep contemplation in which the mind becomes absorbed in its object of meditation. The chapter details progressive stages of samādhi, leading to truth-bearing wisdom (ṛtambharā prajñā, an intuitive knowledge of truth) and finally to nirbīja samādhi, a “seedless” state of complete liberation in which even the final mental impression is dissolved.

This section introduces the central principles of Yoga, defining its goal and the primary methods for achieving it. The book opens with Patañjali's definition of Yoga as the restraint of the modifications of the mind (citta). Author and commentator Satchidananda explains that the mind (citta) is the sum total of the ego, intellect, and desiring faculties. Its natural state is peace, but it is constantly disturbed by thought-waves (vṛttis), which are like ripples on the surface of a lake. When these ripples cease, the mind becomes a clear mirror, and the Seer—the true, unchanging Self (Puruṣa)—abides in its own nature. At all other times, the Self mistakenly identifies with these mental fluctuations, preventing it from recognizing its true nature.

Patanjali categorizes the five types of mental modifications: right knowledge, misconception, verbal delusion, sleep, and memory. He explains that these modifications can be either painful or painless, and Satchidananda illustrates this distinction by comparing selfish thoughts, which ultimately bring pain, with selfless thoughts, which lead to peace. The primary means to restrain these thoughts are twofold: consistent practice (abhyāsa) and non-attachment (vairāgya). Practice must be undertaken for a long time, without interruption, and with earnestness. Non-attachment is the mastery of cravings for worldly objects and experiences. Its highest form is supreme non-attachment, which arises from realizing the Self and causes attachment to worldly pleasures to fall away.

As an alternative path, Patanjali introduces devotion and total surrender to Īśvara, the Supreme Self. Īśvara is described as the supreme, unconditioned Self, the original teacher of all ancient sages, who is unaffected by the afflictions and actions that bind individuals. The word expressive of Īśvara is the mystic sound OM. The practice of repeating OM with an understanding of its meaning (japa) is presented as a method for removing obstacles and directing the mind inward toward realization of the Self.

Patanjali then lists the nine primary obstacles to Yoga practice: disease, dullness, doubt, carelessness, laziness, sensuality, false perception, and the inability to attain or maintain a state of concentration. These distractions are accompanied by symptoms such as distress, despair, trembling, and disturbed breathing. To counteract them, he offers several techniques for calming the mind. One method is cultivating specific attitudes: friendliness toward the happy, compassion for those who are suffering, delight in the virtuous, and disregard toward the wicked. Other practices include controlled breathing (prāṇāyāma), concentrating on subtle sensory perceptions, or meditating on the mind of an enlightened being. Ultimately, Patanjali states that one can achieve stillness by meditating on any suitable object of one's choosing.

The chapter concludes by detailing the advanced stages of samādhi (deep contemplation). As the mind becomes one-pointed, it merges with its object of concentration, losing the distinction between the knower, the known, and the act of knowing. Patanjali outlines a progression of samādhi states, beginning with contemplation on gross objects and moving toward subtler objects of contemplation, ultimately reaching the unmanifest source of nature (Prakṛti). These initial states are called sabija (with seed) samādhi, because the latent impressions of past desires remain and can still lead to bondage. Through deep practice, the yogi attains ṛtambharā prajñā, an intuitive knowledge of truth that transcends knowledge gained from scripture or reason. The impression left by this experience replaces all others. When even this final impression is dissolved, the Yogi achieves nirbija (seedless) samādhi, a state of complete liberation in which the true Self is fully realized.