Patanjali Yoga Sutras Chapter 2: The Real Science of Quieting the Mind

Have you ever wondered why your worst mental habits keep returning, even when you know they hurt you? You promise yourself that you will not lose your temper in traffic, or that you will stop checking your phone the moment you wake up. Yet a few days later, a familiar wave of irritation or anxiety sweeps through, and your rational decisions vanish.

Most modern advice tells us to rely on willpower, positive affirmations, or ten minutes of morning stretching. But if you have tried that, you already know it rarely lasts. Willpower runs out quickly when strong feelings take over.

I used to read Patanjali's Yoga Sutras as a collection of mystical sayings or a guide to physical exercise. But when you sit down with Chapter 2, known as Sādhana Pāda, you find something completely different. It is an honest, practical analysis of how human minds get trapped and how to free them step by step. Patanjali does not ask for blind belief, and he does not offer quick fixes. Instead, he lays out a precise diagnostic method for untangling the knots in our thinking.

Why Chapter 2 Begins with Agitated Minds

In Chapter 1, Patanjali addressed the rare person whose mind is already calm, quiet, and naturally ready for deep absorption (samāhita-citta). Most of us do not live there. Our thoughts are constantly pulled outward by work, family, social drama, and private worries. Our state of mind is what classical thinkers called vyutthita-citta, an active, distracted mind caught in daily friction.

Chapter 2 was written specifically for people in that second group. That is why it opens not with breath retention or deep meditation, but with what Patanjali calls Kriyā-Yoga, the yoga of practical action.

तपःस्वाध्यायेश्वरप्रणिधानानि क्रियायोगः
tapaḥsvādhyāyeśvarapraṇidhānāni kriyāyogaḥ

Verse 2.1 tells us that practical yoga consists of three things: tapas (willingness to bear discomfort to train oneself), svādhyāya (self-study through honest self-observation and reading core teachings), and īśvarapraṇidhāna (letting go of the stubborn ego by offering our actions to a higher ideal). In verse 2.2, Patanjali explains the twin goals of this practice: to weaken the subconscious roots of suffering (kleśa-tanūkaraṇa) and to prepare the mind for steady stillness (samādhi-bhāvana).

Before you can build high focus, you have to quiet down the subconscious static. If your inner drive is fueled by unresolved anger or deep fear, sitting quietly will only amplify your restlessness.

The Four-Part Diagnosis of Human Suffering

Patanjali organizes Chapter 2 using the same four-step structure that ancient Indian physicians used to diagnose and treat diseases (cikitsā-vyūha). Instead of treating bodily fevers, Patanjali applies this diagnostic method to the chronic discomfort of the human mind.

The first step is Heya, identifying what must be prevented. In verse 2.16, Patanjali writes:

हेयं दुःखमनागतम्
heyaṃ duḥkhamanāgatam

This means the suffering that has not yet come is the suffering to be avoided. What has already happened cannot be changed. What is happening right now must be met. But the suffering waiting for you tomorrow, produced by your reactive habits today, can be prevented.

Why does Patanjali say in verse 2.15 that to a person of clear vision, all conditioned living feels like friction (duḥkham eva sarvaṃ vivekinaḥ)? He gives four straightforward reasons:

1. Pariṇāma-duḥkha (suffering from change): Every pleasant situation changes or ends. The car you loved gets scratched, the vacation ends, and your favorite meal is finished. The loss leaves a quiet sting.
2. Tāpa-duḥkha (suffering from anxiety): While enjoying something good, a part of your mind worries about losing it, or feels jealous of someone who has more.
3. Saṃskāra-duḥkha (suffering from memory grooves): Every experience leaves a subtle trace in your subconscious. Pleasurable experiences build cravings for repetition, creating mental loops that make you feel incomplete without another dose.
4. Guṇa-vṛtti-virodha (conflict among the qualities of nature): The world and our nervous systems shift constantly between calmness (sattva), restless activity (rajas), and heavy inertia (tamas). Because these natural qualities are always shifting, you cannot find permanent rest inside worldly objects.

The second step is Heya-Hetu, the cause of this discomfort. In verse 2.17, Patanjali identifies it:

द्रष्टृदृश्ययोः संयोगो हेयहेतुः
draṣṭṛdṛśyayoḥ saṃyogo heyahetuḥ

The cause of suffering is saṃyoga, the false entanglement between the Seer (draṣṭā, your underlying awareness) and the Seen (dṛśya, your thoughts, feelings, body, and the outside world). When a movie plays on a screen, the screen never gets burned by fires in the film, nor does it get wet from rainstorms. But our awareness has become so glued to the mental movie that every time an angry or fearful thought arises, we feel: "I am angry, I am terrified." Verse 2.24 states plainly that this entanglement is kept alive by fundamental misunderstanding (tasya hetur avidyā).

The third step is Hāna, the end of the problem. Verse 2.25 explains that when that misunderstanding ends, the entanglement dissolves (tad-abhāvāt saṃyogābhāvaḥ). Pure awareness rests in its own independent freedom (kaivalyam).

The fourth step is Hānopāya, the practical path to that freedom. Verse 2.26 points to unwavering discriminative discernment (vivekakhyātir aviplavā). It is the steady ability to see, in real time, the difference between who is watching and what is being watched.

The Five Subconscious Afflictions That Rule Our Behavior

Patanjali does not treat our bad moods or anxious spells as random accidents. In verses 2.3 through 2.9, he breaks down the five deep-rooted afflictions (pañca-kleśa) that govern human distress:

अविद्यास्मितारागद्वेषाभिनिवेशाः क्लेशाः
avidyāsmitārāgadveṣābhiniveśāḥ kleśāḥ

These five afflictions operate like a chain reaction, starting with a basic misunderstanding and ending with deep survival fear:

• Avidyā (Fundamental Misunderstanding): Described in verse 2.4 as the soil (kṣetra) from which all other troubles grow. Verse 2.5 defines it simply: seeing the temporary as permanent, the impure as pure, painful things as sources of real pleasure, and our changing body-mind as the true Self.
• Asmitā (False Sense of Identity): Defined in verse 2.6 as the belief that the capacity to see and the instrument of seeing are the exact same thing (dṛg-darśana-śaktyor ekātmateva). It is the mistake of looking through a pair of spectacles and concluding that you are the glass lenses.
• Rāga (Craving): Defined in verse 2.7 as the hunger that trails after memories of pleasure (sukhānuśayī rāgaḥ). It is not the object itself that hooks you; it is your mind's memory of past pleasure demanding another taste.
• Dveṣa (Aversion): Defined in verse 2.8 as the anger and resistance that trail after memories of pain (duḥkhānuśayī dveṣaḥ). Just like craving, aversion is a backward-looking habit that keeps old grievances alive in the body.
• Abhiniveśa (Clinging to Existence): Defined in verse 2.9 as the instinctive terror of death and destruction that runs by its own momentum (svarasavāhī). Patanjali adds an honest detail: this fear grips even the educated scholar (viduṣo 'pi tathā rūḍhaḥ). Intellectual book knowledge alone cannot dissolve the biological panic of self-preservation.

These five afflictions generate what Patanjali calls the karmāśaya in verse 2.12, the hidden reservoir of actions and impressions. As long as this root remains intact, verse 2.13 tells us, it continues to bear fruit in our birth (jāti), our lifespan (āyus), and our daily share of pleasure and pain (bhoga).

The Five External Limbs of Ashtanga Yoga

To dismantle these afflictions, Patanjali introduces the Eight Limbs (aṣṭāṅga) in verse 2.29. Chapter 2 walks us through the first five, often called the external limbs (bahi-raṅga), because they clean up our relationship with society, body, breath, and senses.

The first limb is Yama (verses 2.30 and 2.31), five ethical boundaries that prevent social friction from disturbing our inner peace. These are non-harming (ahiṃsā), truthfulness (satya), non-stealing (asteya), conservation of vital energy (brahmacarya), and non-hoarding (aparigraha). In verse 2.31, Patanjali emphasizes that when these boundaries are practiced unconditionally, without excuses based on social group (jāti), location (deśa), time (kāla), or circumstance (samaya), they become the Great Vow (mahāvratam). If you lie, steal, or harm people, your mind stays caught in defensive vigilance, making quiet focus impossible.

The second limb is Niyama (verse 2.32), five personal habits that build a clean inner foundation: cleanliness of body and mind (śauca), contentment with what you have (saṃtoṣa), disciplined effort (tapas), self-study and chanting (svādhyāya), and trust in something greater than the ego (īśvarapraṇidhāna).

When disturbing or hostile impulses strike, Patanjali offers an effective psychological tool in verses 2.33 and 2.34: Pratipakṣa-Bhāvanam, actively bringing to mind the opposite perspective.

वितर्कबाधने प्रतिपक्षभावनम्
vitarkabādhane pratipakṣabhāvanam

In verse 2.34, he explains how to break down an aggressive impulse (vitarka):

• How did it happen? Did you commit it directly (kṛta), did you ask someone else to do it (kārita), or did you silently approve when someone else did it (anumodita)?
• What drove it? Was it greed (lobha), anger (krodha), or confusion (moha)?
• How strong was it? Mild (mṛdu), moderate (madhya), or extreme (adhimātra)?

Then comes the mental pivot: you remind yourself that no matter how justified a hateful thought feels in the heat of the moment, its real outcome is always endless suffering and confusion (duḥkhājñānānantaphalā). By clearly reviewing the bitter harvest of your anger, the impulse loses its fuel.

The third limb is Āsana (verses 2.46 to 2.48). Today, many people think of yoga posture as complicated contortions. Patanjali defines it in three simple words:

स्थिरसुखमासनम्
sthirasukham āsanam

A posture is simply that which is steady (sthira) and comfortable (sukham). How do you master it? Verse 2.47 gives the exact instruction:

प्रयत्नशैथिल्यानन्तसमापत्तिभ्याम्
prayatnaśaithilyānantasamāpattibhyām

You master posture through the relaxation of effort (prayatna-śaithilya) and by letting your attention settle into the boundless (ananta-samāpatti). You do not conquer your body by clenching muscles or forcing pain. You find a stable position, drop unnecessary tension, and rest your attention. Verse 2.48 tells us the result: you stop being shaken by physical dualities like heat and cold, pleasure and discomfort (tato dvandvānabhighātaḥ).

The fourth limb is Prāṇāyāma (verses 2.49 to 2.53). Once posture is stable, breath regulation begins. Verse 2.49 defines it as the intentional pause in the movement of inhalation and exhalation (śvāsa-praśvāsayor gati-vicchedaḥ). By observing the breath carefully across space, duration, and count, it becomes prolonged and subtle (dīrgha-sūkṣma). In verse 2.51, Patanjali mentions the spontaneous fourth state (caturthaḥ) that goes beyond focusing on breathing in or out.

The goal of breath control is not just physical stamina. Verse 2.52 tells us that through steady breath practice, the veil that covers our inner clarity is stripped away (kṣīyate prakāśāvaraṇam). Verse 2.53 adds that the mind finally becomes fit for one-pointed concentration (dhāraṇāsu ca yogyatā manasaḥ).

The fifth limb is Pratyāhāra (verses 2.54 and 2.55), the inward turning of the senses.

स्वविषयासंप्रयोगे चित्तस्य स्वरूपानुकार इवेन्द्रियाणां प्रत्याहारः
svaviṣayāsaṃprayoge cittasya svarūpānukāra ivendriyāṇāṃ pratyāhāraḥ

When the senses stop chasing outside objects and mimic the natural stillness of the mind, sensory withdrawal takes place. The ears are not shut with plugs; rather, attention is withdrawn so deeply that sounds no longer provoke mental chatter. Verse 2.55 states that this produces supreme mastery over our sensory drives (tataḥ paramā vaśyatendriyāṇām).

Key Sanskrit Terms Explained

To understand Patanjali without distortion, we need to look at his original Sanskrit terms. English words often carry cultural baggage that flattens the precision of the text:

• Saṃyoga: Often translated as union or connection, but in Chapter 2 it specifically means false entanglement. It is the confused knot where pure awareness mistakes the thoughts and feelings of the mind for its own nature.
• Draṣṭā: The Seer. This is the silent witness of awareness (dṛśimātraḥ). Verse 2.20 reminds us that while the Seer is completely pure and unchanged by what it sees, it appears to look through the lens of changing thoughts.
• Dṛśya: The Seen. This is the entire field of experience, including your physical body, your emotions, your intellect, and the material world. In verse 2.18, Patanjali explains that the Seen exists for two clear purposes: to provide experience (bhoga) and to lead to liberation (apavarga).
• Asmitā: Commonly translated as ego or pride, but it means something much more specific here: the mistaken identity where the power of consciousness conflates itself with the mental instrument it uses to think.
• Abhiniveśa: The deep-seated instinct to survive and the terror of being wiped out. It is an ancient survival drive that flows on its own momentum and holds even thoughtful minds in its grip.
• Karmāśaya: The hidden storehouse of past deeds and psychological grooves. It is where our actions, driven by cravings or fears, leave seeds that wait for the right conditions to sprout.
• Pariṇāma-Tāpa-Saṃskāra-Duḥkha: The fourfold diagnostic formula from verse 2.15 explaining why worldly pursuits always leave a trace of dissatisfaction: decay through change (pariṇāma), underlying anxiety (tāpa), habit loops created by past memories (saṃskāra), and the constant clash among the modes of nature (guṇa-vṛtti-virodha).
• Vivekakhyāti: Unshakable, continuous discriminative discernment. It is the steady awareness that you are the conscious observer, not the thoughts drifting across your mind.
• Pratipakṣabhāvanam: The active discipline of countering a harmful, destructive thought by bringing to mind its opposite, and contemplating the misery it inevitably causes.
• Prayatna-śaithilya: The deliberate loosening of physical effort. It teaches that the body settles into stillness not by straining, but by letting go of chronic physical tension.
• Pratyāhāra: Sensory withdrawal. It happens when the senses pull back from outer triggers and settle into the quiet state of the mind itself.

How the Great Commentators Read the Text

Patanjali's sutras are extremely brief, almost like shorthand lecture notes. Over the centuries, classical masters wrote commentaries to explain the practical mechanics behind each verse.

The earliest and most authoritative commentary is the Vyāsa-Bhāṣya, attributed to Sage Vyāsa. Commenting on verse 2.15, Vyāsa explains Patanjali's fourfold diagnostic framework through the direct lens of Āyurveda:

• Roga (the sickness) corresponds to Heya (the cycle of future suffering).
• Roga-Hetu (the cause of the sickness) corresponds to Heya-Hetu (the false entanglement of the observer and the observed).
• Ārogya (the restored state of health) corresponds to Hāna (liberation, or Kaivalya).
• Bhaiṣajya (the medicine) corresponds to Hānopāya (steady discernment, or Vivekakhyāti).

Vyāsa explains that just as medicine does not invent something artificial but simply removes disease to let the body return to health, yoga does not create a new state. It clears away mental confusion so that awareness can rest in its natural baseline.

Vyāsa also offers the memorable analogy of the eyeball (akṣi-pātra). If a tiny speck of dust falls on the back of your hand, you do not even feel it, because the skin is thick and calloused. But if that exact same speck of dust lands in your eye, it causes immediate, agonizing friction. An ordinary mind is like the back of the hand, dulled by daily noise and numb to subtle agitation. But as a practitioner's mind becomes refined through yoga, it becomes sensitive like an eyeball, noticing the smallest trace of agitation or egoism as friction that needs attention.

On verse 2.54, Vyāsa explains sensory withdrawal using the image of a beehive. When the queen bee takes flight, all the worker bees take to the air behind her. When she lands and rests, all the bees settle down quietly around her. In the same way, our senses do not need to be fought individually. When the mind turns inward and becomes still, the senses naturally follow and settle down.

In the ninth century, Vācaspati Miśra clarified in his Tattva-Vaiśāradī that avidyā is not merely the absence of knowledge. Just as the word "enemy" does not mean a piece of wood or a harmless stranger, but an active opponent, avidyā is an active, structural distortion that projects permanence onto things that decay.

Later, in the sixteenth century, Vijñānabhikṣu wrote in his Yoga-Vārttika about the idea of mutual reflection (pratibimba-vāda). Pure awareness reflects onto the quiet intellect, and the movements of the intellect reflect back onto awareness. Because of this two-way reflection, our thoughts seem conscious, and our consciousness feels as though it is suffering from cold, hunger, or grief.

It is worth noting a fundamental difference between classical Yoga and Advaita Vedānta. In Advaita Vedānta, the material world is ultimately an illusion (māyā). But in Patanjali's Yoga, the material universe (Prakṛti) is completely real and enduring. Matter is not an illusion; what is mistaken is our relationship to it. When you reach liberation (Kaivalya), the world does not disappear into nothingness. You simply step out of the false assumption that your identity is tied to your physical and mental machinery.

Connections Across Classical Sanatan Texts

Patanjali did not create these ideas out of thin air. Chapter 2 brings together insights that run through the entire Vedic tradition:

• The Chariot Allegory in the Kaṭha Upaniṣad (1.3.3–1.3.9):

The Kaṭha Upaniṣad gives the classic Vedic picture of our inner makeup. The Self (Ātman) is the passenger riding in the chariot; the physical body is the chariot; the intellect (buddhi) is the charioteer; the thinking mind (manas) is the reins; the senses (indriyas) are the horses; and worldly objects are the roads. Patanjali's teachings on sensory withdrawal (verse 2.54) and mastering the senses are the direct practical application of this image. When the charioteer holds the reins firmly, the sensory horses stop bolting after every passing distraction.

• The Downward Spiral in the Bhagavad Gītā (2.62–2.63):

In Chapter 2 of the Bhagavad Gītā, Krishna explains how a person loses mental balance. Thinking about sensory objects breeds attachment (saṅga). Attachment leads to burning desire (kāma). Thwarted desire triggers anger (krodha). Anger creates delusion (sammoha). Delusion ruins memory (smṛti-bhraṃśa), and the loss of memory destroys the intellect (buddhi-nāśa). This progression matches Patanjali's breakdown of the afflictions: from fundamental misunderstanding to craving, aversion, and complete loss of clarity.

• Steady Posture in the Bhagavad Gītā (6.11–6.13):

When Krishna describes meditation posture in Chapter 6 of the Gītā, he instructs the practitioner to sit firmly in a clean place, keeping the body, neck, and head upright and motionless without straining. This is the exact scriptural foundation for Patanjali's steady and comfortable posture (verse 2.46).

• The Evolution of Matter in the Sāṅkhya-Kārikā:

Patanjali's understanding of nature draws directly from Sāṅkhya philosophy. In verse 2.19, he classifies the stages of nature's qualities into diversified (viśeṣa), undiversified (aviśeṣa), mark-only (liṅgamātra), and markless (aliṅga). This mirrors the Sāṅkhya cosmology of cosmic evolution from unmanifest nature down to the physical elements.

• Āyurvedic Medicine in the Caraka Saṃhitā:

The fourfold diagnostic method used by Patanjali mirrors the foundational diagnostic framework (nidāna-pañcaka) found in the Caraka Saṃhitā. Both traditions approach healing by diagnosing the root cause rather than putting cosmetic bandages on visible symptoms.

What Real Modern Science Shows

When we look at Chapter 2 alongside modern science, we find two genuine areas of practical overlap:

1. Cognitive Behavioral Therapy and Pratipakṣa-Bhāvanam

In modern clinical psychology, Cognitive Behavioral Therapy (CBT), developed by Aaron Beck, and Rational Emotive Behavior Therapy (REBT), pioneered by Albert Ellis, rely on a technique called cognitive restructuring. When patients suffer from chronic anxiety or depression, therapists teach them to identify automatic dysfunctional thoughts, examine the distorted evidence behind them, and deliberately generate realistic alternative perspectives.

This is remarkably close to Patanjali's technique of Pratipakṣa-Bhāvanam (verses 2.33 and 2.34). Patanjali instructs us to catch an aggressive impulse, categorize whether it was self-initiated, caused, or silently approved, identify its root in greed, anger, or delusion, and clearly reflect on the downstream suffering it causes. Both systems recognize that you cannot quiet an obsessive, destructive thought by wishing it away; you must deliberately build a counter-momentum in your thinking.

2. Respiratory Regulation and the Nervous System

Patanjali's instruction on Prāṇāyāma (verses 2.49 to 2.50) emphasizes making the breath slow, smooth, prolonged, and subtle (dīrgha-sūkṣma). Modern neurocardiology has confirmed the physiological mechanisms behind this practice.

When you intentionally slow your breathing and lengthen your exhalation, you stimulate the vagus nerve. This shifts your autonomic nervous system away from sympathetic fight-or-flight arousal and activates parasympathetic tone. Heart rate variability improves, blood pressure stabilizes, and the reactive alarm center of the brain, the amygdala, quiets down. Sowing rhythm into the breath physically calms the nervous system.

Where the Comparison Holds, and Where It Diverges

It is just as important to be honest about where ancient yoga and modern science do not match.

First, while CBT and Patanjali share a similar method for interrupting negative thoughts, their end goals are entirely different. Modern CBT is designed to help you function better in daily life, manage work stress, and maintain healthy relationships. Patanjali's goal is much more radical: he uses Pratipakṣa-Bhāvanam as an ethical and mental purifier to clear away subconscious baggage, preparing awareness for complete spiritual liberation (Kaivalya).

Second, while slow breathing undeniably calms your heart and brain, Patanjali did not design Prāṇāyāma merely for stress management. In verse 2.52, he states that breath regulation is meant to wear away the veil that hides the inner light of awareness (kṣīyate prakāśāvaraṇam), making the mind capable of single-pointed concentration (dhāraṇā). Modern science explains the biological doorway; Patanjali was interested in what lies beyond it.

Finally, we need to address a popular claim that frequently circulates on social media: the idea that Patanjali proved modern quantum simulation theory, or showed that the physical universe does not exist until someone looks at it.

This claim is flatly incorrect. Patanjali was a firm realist about the physical world. In verses 2.18 and 2.22, he makes it clear that the physical world is real, tangible, and independent of personal imagination. In verse 2.22, he offers a direct refutation of subjective idealism:

कृतार्थं प्रति नष्टमप्यनष्टं तदन्यसाधारणत्वात्
kṛtārthaṃ prati naṣṭamapyanaṣṭaṃ tadanyasādhāraṇatvāt

He argues that when one yogi attains freedom and breaks their personal entanglement with matter, the physical universe does not dissolve for everyone else. It continues to exist because it is shared by all living beings. Claiming that Patanjali thought matter was a computer simulation or a figment of imagination contradicts the Sanskrit text and does a disservice to the rigorous realism of Indian philosophy.

Frequently Asked Questions

Why does Patanjali say that all worldly pleasure is suffering?

Patanjali does not deny that eating good food or spending time with friends feels pleasant. His point in verse 2.15 is that conditioned pleasures are inherently unstable. They end quickly (pariṇāma), they trigger underlying worry about losing them (tāpa), they build subconscious cravings that demand repetition (saṃskāra), and they depend on shifting bodily and mental states. For someone who wants lasting peace, relying on temporary circumstances always leads to friction.

Does Patanjali describe complex gymnastics postures in Chapter 2?

No. Out of 55 verses in Chapter 2, Patanjali devotes only three verses to posture (verses 2.46 to 2.48). He defines posture simply as steady and comfortable (sthirasukham āsanam). He does not describe a single specific physical pose by name. In his system, posture is simply a stable seat that allows the practitioner to sit motionless for long periods without bodily distraction, achieved through the relaxation of effort.

How does Pratipakṣa-Bhāvanam differ from simple positive thinking?

Positive thinking often asks people to ignore real problems and repeat pleasant phrases. Pratipakṣa-Bhāvanam (verses 2.33 and 2.34) is an analytical practice. It requires you to look directly at a destructive impulse, identify its emotional root (greed, anger, or delusion), examine your own degree of involvement, and trace out the exact cycle of suffering that giving in to that impulse will cause. It changes behavior through realistic causal understanding, not wishful thinking.

Did Patanjali teach that the physical world is an illusion?

No. Unlike schools of absolute idealism, Patanjali's Yoga philosophy holds that the physical world (Prakṛti) is completely real and enduring. In verse 2.22, Patanjali explicitly notes that even when an enlightened person achieves liberation, the physical world continues to exist for everyone else. Bondage is not caused by the existence of matter, but by our internal confusion (saṃyoga) that mistakes the body and mind for our true self.

Sources

• Yoga Sutras of Patanjali, Chapter 2 (Sādhana Pāda): Yoga Sutras of Patanjali: original Sanskrit text
• Vyāsa-Bhāṣya on the Yoga Sutras, foundational commentary by Sage Vyāsa.
• Tattva-Vaiśāradī by Vācaspati Miśra, ninth-century commentary on the Sūtras.
• Yoga-Vārttika by Vijñānabhikṣu, sixteenth-century exposition of classical Yoga.
• Kaṭha Upaniṣad, specifically Chapter 1, Section 3, verses 3 to 9 (the Chariot allegory).
• Bhagavad Gītā, specifically Chapter 2 (verses 62 to 63) and Chapter 6 (verses 11 to 13).
• Sāṅkhya-Kārikā of Īśvarakṛṣṇa, classical exposition of Sāṅkhya metaphysics and the tattvas.
• Caraka Saṃhitā, classical Āyurvedic treatise on diagnostic methodology (nidāna-pañcaka).
• Clinical cognitive psychology: cognitive restructuring in Cognitive Behavioral Therapy (CBT).
• Autonomic neurocardiology: research on vagal nerve regulation and respiratory sinus arrhythmia.

This reflects what the text itself says; the modern-science comparisons above are interpretation, not an established finding.