The injunction is that tad viddhi, if you want to understand transcendental subject matter, not material, spiritual... Spiritual is completely unknown to us because we do not know what is spiritual. We are identifying with this body. You do not know even that "I am spirit soul." So where is the possibility of spiritual understanding? One cannot see himself, what he is. He is thinking, "I am this body," exactly like the dog. The dog is thinking, "I am dog." So if I think, "I am American," "I am Indian," where is the difference? There is no difference. Yasyātma-buddhiḥ kuṇape tri-dhātuke (SB 10.84.13). If one thinks that "I am this body," then he's no better than sa eva go-kharaḥ. The animals, they also think like that, "I am this body."
So when one understands that "I am not this body. I'm extra..." That can be understood very easily if we analyze ourselves. I have several times said, beginning from your breathing, you analyze. Take breathing. They say breathing is the life. As soon as the breathing is stopped, no more life. So does it mean that breathing is life? No. Analyze. What is this breathing? It is air. So you can get so much air and put it into a machine, just like, what is called, bellow, and pump it through the nose. It is possible to get life? No. In this way, item by item, you analyze this body. Now you are advanced in laboratory analyzing. Take this breathing, take this blood, take this skin, take this bone. So many things are there, ingredients. Analyze each one of them. Will you find life? Therefore common sense, that this is not life... Life is beyond this, beyond this material. So so-called rascals, they think that this is body, this is life, combination. There are many theories. One of the theories is the combination of this matter, these bones, this blood, this skin, the veins, the stool, the urine, so many things—that combination makes the life. And why don't you put... All these things are available. Why don't you put together and bring life? "That we shall do in future." Just see. What is this proposal? Therefore we are so fools and rascals that we do not know what is spirit, life, spirit. Still, we are passing as big scientist and philosopher, all rascals. Anyone who is thinking, "I am this body," he's a rascal. He's an animal. Sa eva go-kharaḥ. Yasyātma-buddhiḥ kuṇape tri-dhātuke sva-dhīḥ kalatrādiṣu bhauma-ijya-dhīḥ (SB 10.84.13). This is Bhāgavata, practical analysis.