श्लेष्मा पित्तमथ स्वेदो वसा शोणितमेव च। इत्यापः पञधा देहे भवन्ति प्राणिना सदा।।

The senses of perception arise from the sattvic part of the five great beings such as the sky: the eye, ear, nose, tongue and skin are the five senses of perception which are the subtle parts of these five great beings.