There are four methods of acquiring knowledge as mentioned in Srimad-Bhagavatam.

1. Pratyaksha — direct perception
2. Anumana — inference
3. Aitihya — tradition, historical understanding
4. Sabda — spiritual sound, particularly vedic/scriptural

The first method of attaining knowledge is through direct perception (pratyaksha), the knowledge one attains by the experience through material senses. For example, we see using eyes, we hear through ears, we smell through nose, we experience the sense of touch through skin and taste using tongue.

The second method of acquiring knowledge is by inference (anumana) - many things are not visible directly but can be established through inference. For example, by seeing the smoke drifting from a distant mountain one can infer the existence of fire in the mountains, for we know from our previous experience that there cannot be smoke without the existence of fire.

The third method of acquiring knowledge is through tradition (aitihya). We attain knowledge through history since the past happenings are documented in history. The acquisition of knowledge through this process is called aitihya (tradition).

Apart from all these, final way of acquiring knowledge is sabda (spiritual sound). Even if I have not seen an object or incident, but I have heard about that object or incident from an experienced person, I became cognizant after hearing from that person. This process of acquiring knowledge is called sabda (spiritual sound). Just like teacher imparts knowledge through sound and students receive it through sound. Teachers give knowledge through mouth and students receive it through ears but the medium is sound. These are the four principal methods of obtaining knowledge about any object.

In these four evidences, the ten methods of obtaining knowledge in nyaya sastra are summarized. Through logic these 4 evidences can be summarized further. Now one cannot have inference without having prior direct experience, it can be said that inference is within direct perception. On the other hand, knowledge of history comes through the medium of sound. Hence aitihya evidence is contained within sabda evidence. Hence only two methods remain for obtaining knowledge about any object – direct perception and sound.

It is to be noted that four kinds of defects* (confusion, inadvertence, cheating and imperfection of senses) exist in the process of obtaining knowledge through direct perception (pratskya pramana) by conditioned living beings, because of which they cannot obtain perfect knowledge. The essence is that if there is defect in the process of acquiring knowledge then how can one obtain the perfect knowledge by accepting such process. In order to obtain the real and perfect knowledge, the process should also be perfect.. Hence only one method of obtaining knowledge remains - that is sabda (sound). Only by sabda pramana, one can have real knowledge.

Now the question arises, which sabda? Is it of conditioned living beings? No. the sound of realized souls (which is free from four kinds of defects). Their teachings alone can impart us the knowledge of spiritual world (Lord’s Abode) or by following the teachings of Lord Himself we can attain the perfect knowledge. This is called sabda pramana. Our previous acharya Srila Bhaktivinode Thakur has written “amnaya prahah tattvam” meaning the knowledge descending from spiritual lineage is the only method for experiencing the real object. Lord has imparted His Absolute knowledge first to Brahma, who was born from His lotus navel.

Lord is infinite and complete. Nobody can know about Lord until He mercifully gives the knowledge to know Him. Lord is called Absolute (means no one is equal to or greater than Him). There is no other way to know Him except by His mercy.

In 1933, when Srila Bhakti Siddhanta Saraswati Prabhupad desired to make a temple in Mumbai, then our Gurudeva (Srila Bhakti Dayita Madhava Goswami Maharaj) and most revered Srila Bhakti Rakshak Sridhardev Goswami Maharaj headed to Mumbai along with some devotees. They were staying in a rented house in Mumbai. When the head of Theosophical Society came to know about the arrival of saints from Gaudiya Math, he invited them to give a lecture in Theosophical Society, which they accepted.

In his address, Sridhar Dev Goswami Maharaj said that as the owner of wealth is called wealthy, likewise, owner of shakti (potency) is called shaktiman or Bhagavan. It is to be noted that no particular energy has been specified, meaning, Bhagavan is possessor of all the energies. Essence is that Lord is Omnipotent, Infinite and Complete – the one which is called Absolute by Western philosophers; Whom nobody can know nor can attain. If a finite living being says that he has known Lord, then infinite Lord becomes finite. That is why, Infinite is unknown. This is the principle which Sridhar Dev Goswami Maharaj established in his discourse. At the end of lecture, the head of society met Sridhar Dev Goswami Maharaj and said, “Swamiji your discourse was grave but I have a question in my mind.”

“What is the question”, Sridhar Maharaj asked in sweet words.

“Swamiji, you said that nobody can know Lord or obtain Him, then why have you people renounced this world and leading the principles of sacrifice and renunciation. I think that if Lord cannot be obtained, then to undergo renunciation, to follow principles of renunciation is all waste.”

Then Sridhar Maharaj said, “Since Lord is Ominpotent, Infinite and Complete, we can know Him and obtain Him.”

Hearing these words of revered Maharaj, the head was astonished and started saying, “You are making contradicting statements. Either you are a barrister or a lawyer. It is not proper to call you saint in my view because only lawyers can make truth appear as false and false appear as truth. Initially you said that Lord is Infinite and Complete, hence nobody can know Him or obtain Him but now you are saying that since Lord is Infinite, Complete and Omnipotent, He can be obtained and known.

After hearing the head of the society Sridhar Maharaj replied smilingly, “If we obtain the Infinite, Omnipotent and Complete Lord by our power and endeavor then the infiniteness of the Infinite does not remain, the completeness of the Complete does not remain. But if the Infinite and Omnipotent does not have power to let Himself known, then also we cannot call Him Infinite or Omnipotent because He does not have the power to make Himself known.

So the principle is that Infinite, Complete and Omnipotent Lord cannot be known by our own endeavor and power but He can let us know Himself by His mercy. This does not limit the infiniteness of the Infinite, completeness of the Complete and omnipotence of the Omnipotent.

For example the asammordhva* tattva, Lord Sri Krishna made Himself known to Brahma through sound. The initiated (srautiya) Brahma perfected this knowledge (Sri Gayatri jnana) though practice. And after experiencing it himself he imparted this knowledge to Narada and his son, Svayambhu Manu. Svayambhu Manu imparted that knowledge to seven bramha-rishis. In another lineage, the same knowledge was imparted to Vedavyasa by Narada. Vedavyasa gave the same to Madhavacarya and in the spiritual lineage, the same knowledge came down to our spiritual master, Nityalila Pravista Om Vishnupad 108 Srimad Bhakti Dayita Madhav Goswami Maharaj. This is the path to acquire knowledge and the process to know Lord through guru-parampara (spiritual lineage) – this knowledge of Vedas descends from above and hence they are non-different from Supreme Lord. The sabda (sound) that is different from Lord is not capable of making Him known. That is why Vedas are called direct Narayana Himself (vedah narayan saksat).

Srimad-Bhagavad-gita is non-different from Sri Krishna since it has been sung from the Lotus-Lips of Sri Krishna. Hence by taking shelter of Gita, one can experience Sri Krishna. Srimad Bhagawatam is Sri Krishna Himself. Its twelve cantos are compared to twelve limbs of Sri Krishna. By taking shelter of Srimad Bhagawatam one can attain Sri Krishna. Similarly, to know about the embodiment of Transcendental Divine Love, Sri Chaitanya Mahaprabhu, one has to relish Sri Chaitanya Bhagawat (written by Srila Vrndavan Das Thakur, who is an incarnation of Srila Vedavyasa) and Sri Chaitanya Charitamrita (illuminated by the inspiration of Vrindavan-vihari Sri Madan Mohan) in the company of devotees.

Lord is the original spiritual master and Vedic scriptures are the original evidence. Hence we have to take shelter of Lord and His transcendental sound – Vedic scriptures. Only by the mercy of Lord and Vedic scriptures can we know Him, understand Him and attain Him.

asammordhva*- no one equal to Him or greater than Him.