These energies, the external energy, Krsna says, they are separated. Separated means you cannot perceive Krsna directly from this energy. All materialistic scientists, they cannot understand that earth is also Krsna's energy, water is also Krsna's energy, fire is also Krsna's energy. But they are energy, that they can understand. They are accepting... The scientists, they are accepting that these are different energies, but whose energy, that they do not know. Therefore Krsna is explaining herewith that "It is My energy, separated energy."
Lecture on Bhagavad-gita 7.4, Vrindavana, August 10, 1974