Knowledge means how this universe is working, what is the working force, what is the energy. Just like scientists, they are searching out different energies. Just like this earth is floating on weightlessness. Such a huge mass of material body with so many mountains, so many seas, oceans, skyscraper houses, cities, towns, countries, it is floating just like a swab, cotton swab, in the air. So if one understands how it is floating, that is knowledge.
So Kṛṣṇa consciousness means to have all kinds of knowledge. Not that we Kṛṣṇa conscious people are being carried away by some sentiment. No. We have got philosophy, science, theology, ethics, morality, everything—everything that is required to be known in human form of life. So Kṛṣṇa says that "I'll speak to you all about knowledge." So this is Kṛṣṇa consciousness. A Kṛṣṇa consciousness, a Kṛṣṇa conscious person should not be fool. If he is required to explain how these universal planets are floating, how this human body is rotating, how many species of life, how they are being evolved... These are all scientific knowledge. Physics, botanics, chemistry, astronomy, everything. Therefore Kṛṣṇa says, yaj jñātvā, if you understand this knowledge, Kṛṣṇa consciousness, then you'll have nothing to know. That means you'll have complete knowledge. We are hankering after knowledge, but if we are in knowledge of Kṛṣṇa consciousness, if we know Kṛṣṇa, then all knowledge is included.