Sanskrit
भूमिरापोऽनलो वायुः खं मनो बुद्धिरेव च । अहङ्कार इतीयं मे भिन्ना प्रकृतिरष्टधा ॥ ४ ॥
bhūmir āpo'nalo vāyuḥ khaṃ mano buddhir eva ca ahaṅkāra itīyaṃ me bhinnā prakṛtir aṣṭadhā
Translation
Earth, water, fire, air, ether, Mind, and Reason also and Egoism—these are the eightfold division of My nature.
Annie Besant · The Bhagavad-Gita, translated by Annie Besant (4th ed., 1922) — Wikisource · Public Domain
Explanation
The lower nature (aparā prakṛti) is enumerated as eight categories: the five gross elements plus mind, intellect, and ego — essentially the raw material of both the physical world and ordinary individual psychology. This is a departure from the ethical and personal focus of chapters 2-6; here Krishna is doing cosmology, laying groundwork that verse 5 completes by naming what this eightfold list leaves out.