Indian man (2): How could I know the unknown within the known?
Prabhupāda: This is already explained. How could you know your great-grandfather? From the paramparā system. Your father says, "Yes, I had my grandfather." So from the authority of your father you can understand. This is easy process. Evaṁ paramparā-prāptam imaṁ rājarṣayo viduḥ (BG 4.2). You have to hear. Therefore Veda is called śruti. Śruti means you have to hear from the right source. Then you know. That is knowledge. You don't hear from a cheater. You hear from the right source. Then the knowledge is perfect.