We have tried to describe in our Easy Journey to Other Planets anti-material, material and anti-material. So that world, the spiritual world, there is, if you go beyond this covering of the sky. You cannot touch even the ultimate covering even, Brahmaloka. We can see there is a covering round, what is called? Horizon. That is covering. This covering is covered by seven layers—same earth, water, fire, ether. One layer is ten times bigger than the other layer. If you can penetrate and go through, then there is the other world, spiritual world. So this is the position. We should be clever enough to understand the constitution of this material world, this material body, and the spirit soul, how the spirit soul can be liberated, how the spirit soul can go to the spiritual world and live there eternally. Everything is very nicely described in the Bhagavad-gītā. Tyaktvā dehaṁ punar janma naiti mām eti kaunteya (BG 4.9). Everyone can go. Mad-yājino 'pi yānti mām (BG 9.25).
So our endeavor should be, instead of being attached to this false enjoyment like cats and dogs, like the animal is running after the false water, the human life is meant for understanding that "The animal is running after false water. Why I shall go there? I am not animal." That is human life. If one, like the cats and dogs and deer, animal, runs after the false water and he dies, struggle for existence. . . "Survival of the fittest," they say. Nobody will survive. So there is no question. If you take the word in a real sense, survival of the fittest, one who has understood that he is not this body, he is spirit soul, he is fit to survive. Otherwise, bhūtvā bhūtvā pralīyate (BG 8.19), you will run after this false thing, and this body will be finished, and again you will have to accept another body, and again you will run after, bhūtvā bhūtvā pralīyate. This is going on. After false thing. Therefore the śāstra says that this human form of life is not meant for running after this false thing. They must understand what is reality. And how to attain that reality? Exactly in the same way: intelligent man knows that "This is my diseased condition. How to get out, achieve that healthy condition? Because I am eternal," na hanyate hanyamāne śarīre (BG 2.20).