To exercise the power of discrimination, man is endowed with Buddhi (the intellect). The intellect has to be unwavering and steady. Man fails to use this discrimination power properly and fully because of his qualities of attachment and aversion (raaga and dwesha), his obliviousness to his inherent divinity and his preoccupation with mundane desires. If these tendencies are removed, the intellect will come into its own as an instrument of discrimination.
The intellect is the highest among man's endowments starting with the body. Above the body are the senses. Subtler than the senses is the mind. The intellect is subtler than the mind. Above the intellect and much more subtle is the Self (Atma). Because of its proximity to the Atma, the Buddhi is very subtle.
(Sanathana Sarathi, November 1997, pg 295)
