s also acceptable.
Syamasundara dasa: Because I understand that I think, I can establish existence of my soul beyond all doubt.
Srila Prabhupada: Everyone thinks. Everyone is there, and everyone has a soul. There are countless souls, and this has to be accepted.
Syamasundara dasa: What about a blade of grass, for instance?
Srila Prabhupada: Yes, it has a way of thinking. That has to be accepted. It is not that we have souls and that the grass has no soul, or that animals have no souls. Jagadish Candra Bose has proved by a machine that plants can feel and think. "I think, therefore I am" is a good proposition because everyone thinks and everyone exists. There are 8,400,000 species of living entities, and they are all thinking, and they all have individual souls.
Hayagriva dasa: There is a lot of conjecture in Descartes concerning the location of the soul. In his Meditations, he writes: "Although the soul is joined to the whole body, there is yet a certain part in which it exercises its functions more particularly than in all the others; and that is usually believed to be the brain, or possibly the heart; the brain, because it is with it that the organs of sense are connected, and the heart because it is apparently in it that we experience the passions." Descartes then goes on to conclude that the soul is situated in a small appendage of the brain called the pineal body.
Srila Prabhupada: This speculation means that he has no definite information. Therefore we have to accept God's instructions. In Bhagavad-gita, Krsna specifically states:
hrd-dese 'rjuna tisthati
"The Supreme Lord is situated in everyone's heart, O Arjuna." (Bg. 18.61) There are two kinds of isvaras, controllers. One is the individual living entity, the jiva, and the other is the Supreme Living Being, the Paramatma, or Supersoul. From the Vedas, we understand that both are sitting together within this body, which is compared to a tree. Both the Supersoul and the individual soul are living within the heart.
Hayagriva dasa: But at the same time, doesn't the soul pervade the whole body?
Srila Prabhupada: Yes. That is also explained in Bhagavad-gita:
yatha prakasayaty ekah
krtsnam lokam imam ravih
ksetram ksetri tatha krtsnam
"O son of Bharata, as the sun alone illuminates all this universe, so does the living entity, one within the body, illuminate the entire body by consciousness." (Bg. 13.34) This is the illumination of the soul. It is like the sun, which is situated in one particular location, yet its illumination is spread everywhere. Similarly, although the soul is situated within the heart, his illumination is characterized by what we call consciousness. As soon as the soul leaves the heart, consciousness is immediately absent from the entire body. At one moment, there may be consciousness, and at the next moment there may be no consciousness at all. When there is no consciousness, one may hack the body to pieces, and no pain will be felt. This is because something is missing, and that something is the soul. When the soul is gone, consciousness is absent from the body. Both the individual soul and individual consciousness are immortal. Under the influence of maya, the illusory energy, our consciousness is absorbed in many material things: society, nationality, sex life, speculation, and so forth. Krsna consciousness means purifying the consciousness so that it will remain fixed only on Krsna.
Hayagriva dasa: Descartes writes: "I know that brutes do many things better than we do, but I am not surprised at it; for that also goes to prove that they act by force of nature. If they could think as we do, they would have an immortal soul as well as we. But this is not likely, because there is no reason for believing it of some animals without believing it of all, and there are many of them too imperfect to make it possible to believe it of them, such as oysters, sponges, etc."
Srila Prabhupada: First of all, living entities do not act by force of nature, but by force of God. Even in the heart of the brute, God is also present. God is within all, and He gives u