Controlled by Three Modes of Nature
Men and other living entities within this cosmic manifestation are controlled by the three modes of nature. For the living entities controlled by the base qualities of nature—passion and ignorance—there is no possibility of understanding God. Even those in the mode of goodness, like the many demigods and great rsis described in these verses, cannot understand the activities of the Supreme Personality of Godhead. As stated in the Bhagavad-gita, only one who is situated in devotional service to the Lord, and who is thus transcendental to all material qualities, can understand Him (bhaktya mam abhijanati [Bg. 18.55]).
Ordinary philosophers can never know the Lord. The great devotee Bhismadeva confirms this in the following statement to Maharaja Yudhisthira (Srimad-Bhagavatam 1.9.16):
O king, no one can know the plan of the Lord, Sri Krsna. Even though great philosophers inquire exhaustively, they are bewildered. No one, therefore, can understand God by speculative knowledge. Indeed, by speculation one will be bewildered.

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