When buddhi [higher intelligence, intellect] soars high, tearing the veils of delusion, one rises above all intellectual pursuits. The teachings that may be encountered from outside are already accessible through buddhi and are fully grasped. All knowledge is known to such a one, and he attains the highest state of yoga. When buddhi is fully developed, one has freedom from the mire of delusion, for he has unalloyed knowledge. Pure buddhi is able to unfold all the secrets of the universe, and all the feebleness and conflicts of the mind are resolved.
The lower mind (manas) is that part of the mind which functions by employing the senses to receive knowledge from the external world and employing the organs of action to act upon the external worlds. All sense perceptions are filtered in a system of conceptualization. A disorganized and uncontrolled mind does not have exact perceptions and thus cannot conceptualize or act accurately. A clouded mind that learns to consult and seek the counsel of buddhi and forms the habit of not initiating action without a decision from buddhi is a well-controlled mind, and it can conceptualize and act in a useful, efficient, and harmonious way. When the lower mind, with the help of sadhana, constantly listens to buddhi with one-pointedness, there is no danger of committing errors.
There are two different states of buddhi: lower buddhi and higher buddhi. The lower buddhi gives diverse instructions one after another, but with its pure reason the higher buddhi gives firm instruction for the benefit of the whole being. It is aware of the source of consciousness within and at the same time has discriminatory knowledge of the external world.