Speaker: Srila Prabhupada
Source: Teach What Krsna has Said

frogstorySo we have to follow mahajana because we are tiny living entities. We cannot speculate. This is nonsense. Speculation is nonsense. Panthas tu koti-sata-vatsara-sampragamyo vayor athapi manaso [Bs. 5.34]. If we speculate we shall never reach the Absolute Truth. That is not possible. But power is very limited. How long I shall speculate? This is called kupa-manduka-nyaya. Just like a frog in the well is informed by his friend, “My dear friend, Mr. Frog, or Dr. Frog, I have seen a big, vast mass of water, Atlantic Ocean.” The frog, he has never seen the Atlantic Ocean. So he is speculating, “Atlantic Ocean? The well is three feet round. It may be four feet.” “No, no. It is very…” “All right, five feet? Six feet? Ten feet?” So how long he will speculate? There is no comparison. Similarly, the greatness of God we cannot speculate. That is not possible.