Bhāgavata says Kṛṣṇa consciousness is not possible for persons who are limited by certain boundary, including universal concept of life. That is also boundary. And matir na kṛṣṇe svataḥ. Svataḥ means by his personal mental speculation. Just like many philosophers are thinking to reach the Absolute Truth beyond this limitation. That is called svataḥ, by personal speculation.
Svataḥ, parataḥ. Parataḥ means from authorities. From spiritual master, from scriptures, from authoritative books, authoritative source of knowledge, that is called parataḥ. Matir na kṛṣṇe parataḥ svato vā mitho. Mitho means by great assembly. Just like the United Nation is trying to solve the problem for the last many years, twenty to twenty-five years, all the nations. This is called mithaḥ, assembly. Mithaḥ means assembly.
So why it is not possible? Because they are limited.