In plain words
He can fly even in the air. Today we see birds. Only because they have two wings and a tail do they move about in the sky. If it has wings and no tail, it cannot move about in the sky. If it has a tail and no wings, it cannot fly in the sky. That is why, for Buddhi to attain all-pervasiveness, Buddhi attains its sacred, subtle form only by the support of these, Ṛta, Satya and yoga. That is why they said, 'Buddhigrāhyamatīndriyaṃ'.
If man today asks himself whether Buddhi is greater or the intellect is greater, from the scholar down to the common man they decide that the intellect is greater. But neither Vedānta nor the Upaniṣads accept this. It holds that the intellect is far smaller than Buddhi. It has decided that the intellect is of no use at all. Once upon a time Vikramāditya held an assembly on whether Buddhi is greater or the intellect is greater. Many scholars, all of them, held that the intellect was greater. Vikramāditya stood up. 'An intellect without āstha and svāstha is useless,' he said. Āstha means simply a kind of keen interest. Svāstha means steadiness. 'What use can there be in an intellect here that has no keen interest and no steadiness?' he concluded. In the intellectuals of today steadiness is to be seen nowhere. There is steadiness in the ordinary man, but in intellectuals there is no steadiness at all. They think they are great intellectuals, but to them it is all nothing but doubt. These are the effects of the intellect. They believe in nothing. What use is such an intellect, without faith? So what has steadiness: that is Buddhi. What is joined with keen interest: that is Buddhi. What is united with Ṛta: that is Buddhi. What is united with Satya: that is Buddhi. What is joined with yoga: that is Buddhi. What is united with śraddhā: that is Buddhi. Can this Buddhi, with so many sacred qualities, be compared in any way with the intellect?
So it is far better for the people of today to be men of Buddhi than intellectuals. A man of Buddhi has humility and obedience. He has faith and steadiness. In intellectuals humility and obedience are not to be seen at all. In intellectuals Ahaṅkāra keeps lodging itself. Ahaṅkāra is subtler still than Buddhi. Ahaṅkāra corrupts even Buddhi. So, giving no room to Ahaṅkāra, we must follow Buddhi and try to understand divinity. The great intellects of that day gave importance to Buddhi alone.