The only thing that doesnt change is change itself.

She is naked and dark like a threatening rain cloud. She is dark, for she who is herself beyond mind and speach, reduces all things into that worldly "nothingness" which as the Void of all which we now know, is at the same time the All (purna) which is Light and Peace. . . . She stands upon the white corpse-like body of Shiva. He is white because He is illuminating transcendental aspect of Conciousness. He is inert because he is the changelss aspect of the Supreme, and she apparently changing aspect of the same. In truth, she and he are one and the same, being twin aspects of the One who is changelessness in, and exists as, change.

[quote by Sir John Woodroffe in the book "Kali - black godess of dakshineswar" by Elizabeth U. Harding]