Last day we were discussing about the process of understanding Bhagavad-gītā. This is to receive the knowledge in disciplic succession, bona fide disciplic succession. It is not a thing... Any knowledge, even material knowledge, if it is not received in bona fide disciplic succession, that knowledge is not perfect. Suppose if you want to be a lawyer, or if you want to be an engineer, or a medical practitioner. You have to receive the knowledge from the authoritative lawyer, authoritative engineer. Of course, I do not know what is the custom here. In India the custom is that a new lawyer, he has to become an apprentice of an experienced lawyer before he is given the license to practice. That is the Indian system. So any knowledge, unless we receive it through the authoritative sources, it is not perfect. It is not perfect.
There are two kinds of processes of acquiring knowledge. One process is deductive, and the other process is inductive. Those who are student of logic, you know that there are two processes: deductive knowledge and inductive knowledge. Deductive knowledge is considered to be more perfect. And what is that? Just like "Man is mortal." This is a truth, accepted. How man is mortal, nobody's going to enter into discussion. It is accepted that man is mortal. Now, Mr. Johnson is a man. So he is mortal. This is the deductive conclusion. Because man is mortal and Johnson is a man, therefore he's mortal. This is the process of deductive knowledge. Now, how this man is mortal, this truth established? The other party, those who are inductive, follower of inductive process, they want to see actually by experiment and observation how man is mortal. They want to study, "This man dies. That man dies. That man dies. That man dies." Therefore they make a general conclusion, "Well, all men are mortal."
Now, in the inductive process you have got some defects. What is that? Now, your experience is limited. Suppose if you have not seen a man who is not mortal, who is not mortal. There may be. Because you are going on with your personal experience, but your personal experience is always imperfect. That I have already discussed. Because we have got our senses with limited power. And there are so many defects in our conditioned stage. Therefore inductive process is not always perfect. The deductive process, from the authority, the knowledge received, is always perfect. So Vedic process is deductive process. Vedic process is deductive process.
You'll find so many verses in the Bhagavad-gītā which may appear to be dogmatic. The Lord says that mattaḥ parataraṁ nānyat kiñcid asti dhanañjaya: (BG 7.7) "My dear Arjuna, there is nobody else greater than Me. There is no greater authority than Me." Kṛṣṇa says. Now, apparently, it appears very dogmatic. Suppose if I say before you that, "There is nobody greater than me," oh, you'll think, "Oh, Swamiji is very proud." Yes. If a man like me, who is conditioned by so many, I mean to say, restrictions, if I say that I am the greatest of all, that is a blasphemy. I cannot say that. But Kṛṣṇa can say. Because the history of life from Kṛṣṇa, we can understand that actually He was the greatest personality. At least, during His time, He was the greatest personality in every field of activities. Now knowledge received from the greatest personality, greatest authority, is, according to Vedic system, that is accepted as perfect.
There are three kinds of proofs. According to Vedic system, they accept three kinds. For establishing truth, they, they take three kinds of proofs: pratyakṣa, anumāna, aitihya. In logic also, these three kinds of proofs are accepted. What is that? Now, direct perception. You are seeing. I am sitting here. That is direct knowledge. I am seeing that you are sitting here. That is direct knowledge, pratyakṣa.
Anumāna. Anumāna means just like the children are playing there. We are hearing their sound. So we can conjecture that there are some children. We don't see the children. But we can conjecture, we can think, we can imagine that there are some children who are playing there. This is called anumāna.
Pratyakṣa, anumāna and aitihya, or śabda-pramāṇa. Śabda-pramāṇa means to take the truth from the highest authority. That is called śabda-pramāṇa. Just like "Man is mortal." Now, this "Man is mortal," nobody knows wherefrom this sound has come first. Who has experienced that man is mortal? But we are accepting this. We are accepting this. By tradition, we know man is mortal. Now if we, if somebody says, "Who found this truth first? Who discovered that man is mortal?" That is very difficult to say. But it is coming down. The knowledge is coming down, "Man is mortal," and we accept everything. There are so many examples. So out of these three, the Vedic knowledge, they say that this aitihya, or the knowledge received from the authority, is the most perfect.
Neither, I mean to say, imagination or hypothesis nor direct. Direct perception is always imperfect, especially in the conditioned stage of life. Just like direct perception—with our eyes we see the sun just like a disc, not more than your plate on which you take your meals. But from authority, aitihya, we understand the sun is so many millions times greater than this earth. So which of them is right? By seeing your direct perception, sun just like a disc—is it right? Or you take it from authority that sun is such and such times bigger than the earth? Which one of them you'll accept? But you are not going to prove it that the sun is so great. You do not know. You accept from some scientist, from some astronomer, from some authority, that sun is so great. But you have no capacity to see yourself whether the sun is so great or not. Therefore the knowledge received from authority actually we are accustomed and we are accepting this type of knowledge in every field of our activities.
Now, what is this newspaper? Oh, you, from newspaper you understand that "In China such and such things have taken place. And in India such and such things have taken place." Or from radio message you understand that "Such and such things have taken place." But you are not experiencing them directly, whether such and such things have actually taken place. But you accept the authority of the newspaper. You accept the authority of newspaper and you believe it, that in China such and such things have taken place and in India such and such things have taken place, which is far beyond the range of your direct perception. Similarly, there are many instances. We have to believe the authority to take knowledge. And the more the authority is perfect, your knowledge is perfect. The more the authority is perfect, your knowledge is perfect. Direct perception in all cases, it is not possible to receive direct perception of everything.