Unless one is wise, he cannot surrender unto Krsna. Therefore Caitanya-caritamrta says, krsna yei bhaje sei bada catura. Catura means very intelligent. Only the first-class intelligent men in the human society, they can take to Krsna consciousness, not even second class, what to speak of the third class? The third-class men are karmis, the second-class men are philosophers, and the first-class men are devotees.
Lecture on Srimad-Bhagavatam 1.5.12-13, New Vrindaban, June 11, 1969