Bhagavad Gita, Chapter 7, Verse 4

भूमिरापोऽनलो वायुः खं मनो बुद्धिरेव च । अहङ्कार इतीयं मे भिन्ना प्रकृतिरष्टधा

bhūmirāpo'nalo vāyuḥ khaṃ mano buddhireva ca | ahaṅkāra itīyaṃ me bhinnā prakṛtiraṣṭadhā

Translation

Earth, water, fire, air, ether, thought (manas) and reason (buddhi), egoism (ahaṃkāra) — thus is My Prakṛti divided eightfold.

— Alladi Mahadeva Sastri

Word meanings

bhūmiḥ

earth

āpaḥ

water

analaḥ

fire

vāyuḥ

air

kham

ether

manaḥ

mind

buddhiḥ

reason

eva

even

ca

and

ahaṅkāraḥ

egoism

iti

thus

iyam

this

me

of me

bhinnā

divided

prakṛtiḥ

nature

aṣṭadhā

eightfold

Śaṅkarācārya's commentary

Earth stands for the subtile rudimental element or Tanmātra, the Pṛthivī-tanmātra or the subtile rudimental element of earth; and so water, fire, air and ether stand for the Tanmātras of water, etc. Thought (manas) stands for its cause ahaṃkāra or egoism; reason (buddhi) for the Mahat principle, which is the cause of ahaṃkāra; and ahaṃkāra for the Avyakta, the Unmanifested, conjoined with avidyā or nescience. Just as food which is mixed with poison is itself called poison, so the Avyakta, the First Cause, conjoined with the vāsanā, or latent unconscious impression, of ahaṃkāra, is itself called here ahaṃkāra inasmuch as Egoism is the impelling cause of all. As a matter of fact, we find, from our ordinary experience, that egoism is the cause of the activity of every being. Thus divided eightfold is My Prakṛti, the Māyā belonging to the Īśvara.