"Regarding the spiritual science of the self, there are many literatures, such as the four Vedas, the Vedanta-sutra and the Puranas, the Srimad Bhagavatam and the Gita. These are all representatives of Krsna. Among logicians there are different stages of argument. The presentation of evidence is called jalpa. The attempt to defeat one another is called vitanda, and the final conclusion is called vada. The conclusive truth, the end of all reasoning processes, is Krsna."
Bhagavad-gita 10:32 Purport
"When there is a congregation of devotees, their discussions, questions and answers become conclusive to both the speaker and the audience. Thus such a meeting is beneficial for everyone's real happiness.
Purport: Hearing discussions among the devotees is the only means to receive the powerful message of the Supreme Personality of Godhead. For instance, Bhagavad-gita has been well known all over the world for a very long time, especially in the Western world, but because the subject matter was not discussed by devotees, there was no effect. Not a single person in the West became Krsna conscious before the Krsna consciousness movement was founded. But when the same Bhagavad-gita was presented as it is through the disciplic succession, the effect of spiritual realization was immediately manifested.
.....Generally there are two classes of men, the materialist and the transcendentalist. By hearing discussions between devotees, both the materialist and transcendentalist are benefited. The materialist is benefited by association with devotees because his life then becomes regulated so that his chance of becoming a devotee or making the present life successful for understanding the real position of the living entity is increased. When one takes advantage of this opportunity, he is assured of a human form of life in the next birth, or he may be liberated completely and go back home, back to Godhead. The conclusion is that if one participates in a discussion of devotees, he is both materially and spiritually benefited. The speaker and the audience are both benefited, and the karmis and jnanis are benefited. The discussion of spiritual matters amongst devotees is beneficial for everyone, without exception."
Srimad-Bhagavatam 4:22:19
"As far as philosophical speculation is concerned, one philosopher puts forward some theory, then another philosopher puts forward another theory, and the theories always contradict each other. Unless you defeat another philosopher, you cannot be a famous philosopher. That is the way of philosophy. Then how can one learn the conclusive philosophical truth? That is stated: dharmasya tattvam nihitam guhayam. The secret of the religious process is lying within the hearts of the self-realized souls. Then how do you realize it? Mahajano yena gatah sa panthah: You have to follow in the footsteps of great spiritual personalities. Therefore we are trying to follow Lord Krsna and Lord Caitanya. That is perfection. You have to accept the injunctions of the Vedas, and you have to follow the instructions of the bona fide spiritual master. Then success is sure."
Laws of Nature, Text 1
Bhaktivedanta Book Trust. HDG A.C. Bhaktivedanta Swami Srila Prabhupada.