Karandhara. Geologists study the strata of the earth’s crust to trace out the origin of the earth.

Çréla Prabhupäda. But these strata are being created and destroyed at every moment. Now they are one way, and a half hour from now they will be different. They are jagat, always changing. Kåñëa states in Bhagavad-gétä (8.4), adhibhütaà kñaro bhävaù: “Physical nature is known to be endlessly mutable.” Therefore, one cannot find out the source of all energy simply by observing the energy itself. Now the earth’s strata may be black, later they may be white, and then again black. So the geologists study the black color, then the white color, again the black, and so on. This is called punaù punaç carvita-carvaëänäm [SB 7.5.30], “chewing the chewed.”[5] Now it is cold, at midday it will be warm, and at night it will be cold again. In this way, the entire material cosmic manifestation is subject to different types of change. Even our bodies are changing. Everything is changing. But what is the eternity behind this changing? That is the subject of real knowledge. The scientists do not find that eternity, and therefore they are disappointed. They think that the background of everything is void, zero. They think that eternity is zero. And when they are asked where this zero comes from, they say, “It comes from nothing.” So we must ask them, “How have the varieties come about?” The Vedic conclusion is that variety is eternal, although the changing varieties the scientists study in the material world are temporary. These varieties are shadow varieties. Real variety exists eternally in the spiritual world.

Dr. Singh. So the material universe is like a mirage?

Çréla Prabhupäda. Yes. Suppose I think I see water in the desert when there is not water. This is an illusion. Water exists, but not in the mirage. Similarly, the material varieties we see—the varieties of enjoyment—are like that mirage. We, the living entities, are meant for enjoyment, but we are seeking enjoyment in a false place—in an illusion. We are like the desert animals who run after water in a mirage and eventually die of thirst. They cannot relieve their thirst with such illusory water. Similarly, we are trying to manufacture many things to satisfy our thirst for enjoyment, but we are being baffled at every turn because material existence is an illusion. Therefore real intelligence means to inquire, “Where is the reality? Where is the eternal substance behind the illusion?” if we can find that out, we can experience real enjoyment.