Because all of us are bewildered by the illusory external energy of the Supreme Lord, we can see only this manifested cosmos according to our individual ability
SB Canto 2
Since neither Lord Śiva nor you nor I could ascertain the limits of spiritual happiness, how can other demigods know it? And because all of us are bewildered by the illusory external energy of the Supreme Lord, we can see only this manifested cosmos according to our individual ability.
We have many times mentioned the names of twelve selected authorities (dvādaśa-mahājana), of which Brahmā, Nārada and Lord Śiva head the list as the first, second and third in order of merit of those who know something of the Supreme Lord. Other demigods, semi-demigods, Gandharvas, Cāraṇas, Vidyādharas, human beings or asuras cannot possibly know fully about the potencies of the Absolute Lord, Śrī Kṛṣṇa. The demigods, semi-demigods, Gandharvas, etc., are all highly intelligent persons in the upper planets, the human beings are inhabitants of the intermediate planets, and the asuras are inhabitants of the lower planets. All of them have their respective conceptions and estimations of the Absolute Truth, as does the scientist or the empiric philosopher in human society. All such living entities are creatures of the material nature, and consequently they are bewildered by the wonderful display of the three modes of material nature. Such bewilderment is mentioned in the Bhagavad-gītā (7.13). Tribhir guṇamayair bhāvair ebhiḥ samam idaṁ jagat: every entity, beginning from Brahmā down to the ant, is individually bewildered by the three modes of material nature, namely goodness, passion and ignorance. Everyone thinks, in terms of individual capacity, that this universe, which is manifested before us, is all in all. And so the scientist in the human society of the twentieth century calculates the beginning and end of the universe in his own way. But what can the scientists know? Even Brahmā himself was once bewildered, thinking himself the only one Brahmā favored by the Lord, but later on, by the grace of the Lord, he came to know that there are innumerable more powerful Brahmās as well, in far bigger universes beyond this universe, and all of these universes combined together form ekapād-vibhūti, or one fourth of the manifestation of the Lord's creative energy. The other three fourths of His energy are displayed in the spiritual world, and so what can the tiny scientist with a tiny brain know of the Absolute Personality of Godhead, Lord Kṛṣṇa? The Lord says, therefore, mohitaṁ nābhijānāti mām ebhyaḥ param avyayam: (BG 7.13) bewildered by such modes of material nature, they cannot understand that beyond these manifestations is a Supreme Person who is the absolute controller of everything. Brahmā, Nārada and Lord Śiva know about the Lord to a considerable extent, and therefore one should follow the instructions of these great personalities instead of being satisfied with a tiny brain and its playful discoveries such as spacecraft and similar products of science. As the mother is the only authority to identify the father of a child, so the mother Vedas, presented by the recognized authority such as Brahmā, Nārada or Śiva, is the only authority to inform us about the Absolute Truth.