Arjuna said
किं तद् ब्रह्म किमध्यात्मं किं कर्म पुरुषोत्तम ।
अधिभूतं च किं प्रोक्तमधिदैवं किमुच्यते ॥1॥
Arjuna said: What is that Brahman, Purushottama? What is the self? What is action? What is called the realm of matter, and what the realm of the gods?