Having outlined the two major options that can account for the appearance of human consciousness, Sri Aurobindo now explores each of the two to determine how well they each fit with the facts as we can apprehend them. First he takes up what we will call the “evolutionary option” which is essentially based in the concept that human consciousness came about as a progression built upon the basis of animal consciousness. “The necessary condition for the change from the normal animal to the human character of existence would be a development of the physical organisation which would capacitate a rapid progression, a reversal or turnover of the consciousness, a reaching to a new height and a looking down from it at the lower stages, a heightening and widening of capacity which would enable the being to take up the old animal faculties with a larger and more plastic, a human intelligence, and at the same time or later to develop greater and subtler powers proper to the new type of being, powers of reason, reflection, complex observation, organised inventin, thought and discovery.”
Sri Aurobindo points out that the basic aspects of animal consciousness already contain some of the primary capacities needed as the basis for the proposed developments. “…the working of these faculties is more mechanical, less deliberate, marked with the character of an automatism of Nature-Energy driving an operation of primitive consciousness and not, as in man, of a conscious Energy observing and to a great extent directing and governing and deliberately changing or modifying its own operations. Other animal habits of consciousness are not fundamentally different from man’s; all he had to do was to develop and enlarge them on a higher mental level and wherever possible, to mentalise, refine, subtilise,–in brief, to bring to them the enlightenment of his new understanding and intellectual capacity and a power of reasoned control denied to the animal.”
The turning back and working upon the preceding gradation of manifestation is an established principle of Nature, which we see as Life-Energy turns back and works upon Matter; and as the Mental Consciousness as expressed in the animal works upon Life-Energy and Matter. So it is consistent with Nature’s methodology for the human consciousness to turn back and work upon the preceding levels, as we see actually does occur.
Sri Aurobindo, The Life Divine, Book 2, Part 2, Chapter 23, “Man and the Evolution”