This aphorism introduces the concepts of transformation and modification, which are attributes of Prakriti. Transformation denotes change into another substance, like a tree that changes sunlight, water, and earth into fruit. Modification implies that the substance retains its character while appearing in different forms, like a plate, cup, etc., which are different forms of clay. While the modifications of the principles produce the seemingly infinite variety of nature, the transformations are finite in number.
3. Transformation is numerically sixteen only
vikarah: transformation, modification, evolute, product
The sixteen transformations include the eleven Indriyas, which evolve from Ahamkara, and the five gross elements, which are the products of the Tan-Matras.
The Indriyas or Instruments are categorized as instruments of cognition or perception, and instruments of action. The five instruments of cognition include the powers located in the eyes, ears, nose, tongue, and skin. The five instruments of action include the powers located in the hands, feet, voice, anus, and genitals. The eleventh Indriya, Manas or mind, has properties of both cognition and action.
The five gross elements include earth, water, fire, air, and akasa or ether. The term gross here means having an attribute that is directly perceptible by the external senses. Time and space are forms of akasa, a term unfamiliar to most Americans.
The transformations differ from the prakritis in the sense that they are evolutes or effects only. They do not evolve further into other effects.