In the material science you cannot conceive that a thing simultaneously positive and negative. That you cannot think. That is inconceivable energy. And because everything is Kṛṣṇa's energy, Kṛṣṇa can manifest Himself from any energy, and act. Therefore, when we worship Kṛṣṇa made of something of earth, water, or something like that, that is Kṛṣṇa, that is not Kṛṣṇ... You cannot say it is not Kṛṣṇa. When you worship this metal form of Kṛṣṇa, that is Kṛṣṇa. That's a fact. Because metal is energy of Kṛṣṇa. Therefore it is non-different from Kṛṣṇa. And Kṛṣṇa's so powerful that He can present Himself fully in His energy. So this Deity worship is not heathenism. It is actually worshiping God, provided you know the process.
Bob: If you know the process, then the Deity becomes Kṛṣṇa?
Prabhupāda: Yes. Not becomes, it (is) Kṛṣṇa.
Bob: The Deity is Kṛṣṇa.
Prabhupāda: Yes.
Bob: But only if you know the process of it.
Prabhupāda: Yes. Just like this electric wire is Kṛṣṇa..., er, is electricity. One who knows the process he can derive electricity out of it.
Śyāmasundara: Otherwise it's just wire.
Prabhupāda: That's all.
Bob: So if I build a statue of Kṛṣṇa, it is not Kṛṣṇa. But if I, unless I know the process...
Prabhupāda: No, it is Kṛṣṇa. But you have to know the process that it is Kṛṣṇa. It is Kṛṣṇa.
Bob: It is not just earth and mud, it is Kṛṣṇa...
Prabhupāda: No, earth... Earth has no separate existence without Kṛṣṇa. Kṛṣṇa says, "It's my energy." You cannot separate the energy and the energetic. It is not possible. You cannot separate heat from fire. But fire is different from the heat. And heat is different from the fire. You are taking heat, that does not mean you are touching fire. Fire, in spite of expanding heat, it keeps its identity. Similarly, Kṛṣṇa by His different energies creating everything, He remains Kṛṣṇa. The Māyāvādī philosophers, they think, "If Kṛṣṇa is everything, then Kṛṣṇa's separate identity is not there." That is material thinking. Just like drinking this milk, so little, little, when I finish, there is no more milk. It has gone to my belly. Kṛṣṇa is not like that. Because He's omnipotent, we are utilizing His energy continually, but still He's there, present. Just like a man begetting children unlimitedly, but the man is there. Crude example. But not that because he has produced hundreds of children, therefore he is finished. So similarly, God or Kṛṣṇa, in spite of His unlimited number of children, He's there. Pūrṇasya pūrṇam ādāya pūrṇam eva avaśiṣyate (Iso Invocation). This is Kṛṣṇa consciousness. Kṛṣṇa is never finished.