Professor: Well, that brings that to my original question again. How do I know who is perfect?
Prabhupāda: That is another thing, that you have to search out such person. Otherwise your knowledge is imperfect. Now that question will be: "How to find out such person?" The next question will be. But unless you approach such perfect person, you cannot have perfect knowledge. That is a fact. Therefore the conclusion is that we should not speculate about perfect knowledge, but we should try to approach the perfect person and receive knowledge from him. This is the conclusion.
Professor (Hṛdayānanda): He's more or less saying that in the Catholic church how they also demand the same type of faith. He said they all have a bad experience with that. And then he more or less...
Prabhupāda: No, no, I can understand. The thing is that everyone can take advantage of this statement that "I am perfect." Just like so many rogues and bogus persons come. But it is your duty to know whether he is perfect. It is your duty to test whether he is perfect. That requires intelligence. If you unintelligently accept some bogus person as perfect, that is your fault. You must be assured that "The person from whom I am asking, he is perfect." Then you take it. Otherwise don't take.
Professor: Can I put a question? Why do you always say, "From a perfect person"?
Prabhupāda: Because the knowledge must be perfect; otherwise imperfect knowledge.
Professor (Hṛdayānanda): He's saying why do you say a perfect person instead of saying a perfect philosophy?
Prabhupāda: No, unless the philosophy is given by a perfect person how the philosophy can be perfect? Philosophy means searching after the truth. So if he does not know how to find out the truth, what is the meaning of his philosophy? I was a student of philosophy. My professor was Dr. Urquhart. He used to say that "Philosophy is the science of science." So unless he is a perfect scientist, how he can give science?