The Lord's supervision in connection with creation is mentioned even in the Bhagavad-gītā (9.10), and it is clearly said there that material energy is a manifestation of one of many such energies of the Supreme (parāsya śaktir vividhaiva śrūyate (Cc. Madhya 13.65, purport)). An inexperienced boy may be struck with wonder by seeing the impersonal actions of electronics or many other wonderful things conducted by electrical energy, but an experienced man knows that behind the action is a living man who creates such energy. Similarly the so-called scholars and philosophers of the world may, by mental speculation, present so many utopian theories about the impersonal creation of the universe, but an intelligent devotee of the Lord, by studying the Bhagavad-gītā, can know that behind the creation is the hand of the Supreme Lord, just as in the generating electrical powerhouse there is the resident engineer.
(Srimad Bhagavatam------2:4:6-----purport).

Those who are on the path of self-realization are generally classified as karmīs, jñānīs, yogīs, or devotees of the Lord. The karmīs, who are much attracted by the fruitive activities of the Vedic rituals, are called bhukti-kāmī, or those who desire material enjoyment. The jñānīs, who try to become one with the Supreme by mental speculation, are called mukti-kāmī, or those who desire liberation from material existence. The mystic yogīs, who practice different types of austerities for attainment of eight kinds of material perfection and who ultimately meet the Supersoul (Paramātmā) in trance, are called siddhi-kāmī, or those who desire the perfection of becoming finer than the finest, becoming heavier than the heaviest, getting everything desired, having control over everyone, creating everything liked, etc.
(Srimad Bhagavatam------2:4:19-----purport).

The pure devotee, however, by following the ways of previous ācāryas, or authorities, can see the Supreme Lord through the transparent medium of a bona fide spiritual master (anupaśyanti). The pure devotee never tries to see the Lord by mental speculation, but by following in the footsteps of the ācāryas (mahājano yena gataḥ sa panthāḥ (CC.2:17:186). Therefore there is no difference of conclusions amongst the Vaiṣṇava ācāryas regarding the Lord and the devotees. Lord Caitanya asserts that the living entity (jīva) is eternally the servitor of the Lord and that he is simultaneously one with and different from the Lord. This tattva of Lord Caitanya's is shared by all four sampradāyas of the Vaiṣṇava school (all accepting eternal servitude to the Lord even after salvation), and there is no authorized Vaiṣṇava ācārya who may think of the Lord and himself as one.
(Srimad Bhagavatam------2:4:21-----purport).

Anyone, therefore, who is earnestly serious in heart and soul about being in intimate touch with the Personality of Godhead in the relationship of transcendental loving service will always be infallible in words and action. The reason is that the Supreme Lord is Absolute Truth, and anything earnestly dovetailed with the Absolute Truth attains the same transcendental quality. On the other hand, any amount of mental speculation on the strength of material science and knowledge without any bona fide touch with the Absolute Truth is sure to be a mundane untruth and failure, simply due to not being in touch with the Absolute Truth. Such godless, unfaithful words and actions, however materially enriched, are never to be trusted. That is the purport of this important verse. A grain of devotion is more valuable than tons of faithlessness.
(Srimad Bhagavatam------2:6:34-----purport).

The impersonal and personal conceptions of the Lord are existing simultaneously, and this fact is clearly described both in the Bhagavad-gītā and in the Śrīmad-Bhāgavatam, and also in other Vedic scriptures. Inconceivable to human intelligence, the idea must simply be accepted on the authority of the scriptures, and it can only be practically realized by the progress of devotional service unto the Lord, and never by mental speculation or inductive logic. The impersonalists depend more or less on inductive logic, and therefore they always remain in darkness about the original Personality of Godhead Śrī Kṛṣṇa. Their conception of Kṛṣṇa is not clear, although everything is clearly mentioned in all the Vedic scriptures. A poor fund of knowledge cannot comprehend the existence of an original personal form of the Lord when He is expanded in everything. This imperfectness is due, more or less, to the material conception that a substance distributed widely in parts can no longer exist in the original form.
(Srimad Bhagavatam------2:6:39-----purport).

Perfect civilization is the civilization of ātmā, or the soul proper. The civilized man of sense gratification is on an equal level with animals because animals cannot go beyond the activities of the senses. Above the senses is the mind. The civilization of mental speculation is also not the perfect stage of life because above the mind is the intelligence, and the Bhagavad-gītā gives us information of the intellectual civilization. The Vedic literatures give different directions for the human civilization, including the civilization of the senses, of the mind, of the intelligence, and of the soul proper. The Bhagavad-gītā primarily deals with the intelligence of man, leading one to the progressive path of civilization of the spirit soul. And Śrīmad-Bhāgavatam is the complete human civilization dealing with the subject matter of the soul proper. As soon as a man is raised to the status of the civilization of the soul, he is fit to be promoted to the kingdom of God, which is described in the Bhagavad-gītā as per the above verses.
(Srimad Bhagavatam------2:7:18-----purport).

One cannot manufacture a God by one's mental speculation or by numerical votes, as has become a practice for the less intelligent class of men. God is God eternally, and an ordinary living entity is eternally a part and parcel of God. God is one without a second, and the ordinary living entities are many without number. All such living entities are maintained by God Himself, and that is the verdict of the Vedic literatures. When Kṛṣṇa was on the lap of His mother, the demon Pūtanā appeared before His mother and prayed to nurture the child in her lap. Mother Yaśodā agreed, and the child was transferred onto the lap of Pūtanā, who was in the garb of a respectable lady.
(Srimad Bhagavatam------2:7:27-----purport).

Certainly it is not by mental speculation, nor by any attempt by dint of limited instruments of knowledge. By the limited instruments of knowledge (either the senses or the material instruments like microscopes and telescopes) one cannot even fully know the Lord's material potencies, which are manifested before our eyes. For example there are many millions and billions of planets far, far beyond the scientist's calculation. But these are only the manifestations of the Lord's material energy. What can the scientist hope to know of the spiritual potency of the Lord by such material efforts? Mental speculations, by adding some dozens of "if's" and "maybe's," cannot aid the advancement of knowledge—on the contrary, such mental speculations will only end in despair by dismissing the case abruptly and declaring the nonexistence of God. The sane person, therefore, ceases to speculate on subjects beyond the jurisdiction of his tiny brain, and as a matter of course he tries to learn to surrender unto the Supreme Lord, who alone can lead one to the platform of real knowledge. In the Upaniṣads it is clearly said that the Supreme Personality of Godhead can never be known simply by working very hard and taxing the good brain, nor can He be known simply by mental speculation and jugglery of words.
(Srimad Bhagavatam------2:7:43-45-----purport).

The example of Indra is very appropriate in this connection. King Indra of heaven is the controlling deity or demigod for arranging clouds and supplying rains in the universe, and as such he does not have to take the trouble to dig a well for his personal water supply. For him, digging a well for a water supply is simply ludicrous. Similarly, those who are factually engaged in the loving service of the Lord have attained the ultimate goal of life, and for them there is no need of mental speculation to find out the true nature of God or His activities. Nor do such devotees have to meditate upon the imaginary or real identity of the Lord. Because they are factually engaged in the transcendental loving service of the Lord, the Lord's pure devotees have already achieved the results of mental speculation and meditation. The real perfection of life is therefore to be engaged in the transcendental loving service of the Lord.
(Srimad Bhagavatam------2:7:48-----purport).

The Bhāgavatam in a nutshell, spoken by the Personality of Godhead in about half a dozen verses, which will appear ahead, is the science of God, and it is the potent representation of the Personality of Godhead. He, being absolute, is nondifferent from the science of God, Śrīmad-Bhāgavatam. Brahmājī received this science of Godhead from the Lord directly, and he handed over the same to Nārada, who in his turn ordered Śrīla Vyāsadeva to expand it. So the transcendental knowledge of the Supreme Lord is not mental speculation by the mundane wranglers, but is uncontaminated, eternal, perfect knowledge beyond the jurisdiction of material modes.
(Srimad Bhagavatam------2:7:51-----purport).

Thus the knowledge, being received from the chain of disciplic succession, is perfect. One cannot be a spiritual master in perfection unless and until one has received the same by disciplic succession. That is the secret of receiving transcendental knowledge. The six great sages mentioned above may be great thinkers, but their knowledge by mental speculation is not perfect. However perfect an empiric philosopher may be in presenting a philosophical thesis, such knowledge is never perfect because it is produced by an imperfect mind. Such great sages also have their disciplic successions, but they are not authorized because such knowledge does not come directly from the independent Supreme Personality of Godhead, Nārāyaṇa.
(Srimad Bhagavatam------2:8:25-----purport).