We generally characterize the major difference in psychology between animals and human beings as the result of the ability of the human being to utilize the Reason, a higher form of intelligence than the basic sense apparatus and physical mind that clearly is predominant in the animal consciousness. At the same time, we can see elements of the power of Reason in the animal kingdom, and cannot deny that most human beings utilize the sense and physical mind capacities as their primary tool for navigating their way through their lives.
Sri Aurobindo points out that “…reason is only a particular and limited utilitarian and instrumental activity that proceeds from something much greater than itself, from a power that dwells in an ether more luminous, wider, illimitable.” There appears to be actually a ladder of consciousness which does not provide clearly defined separate steps between the animal and man, and which has not finished its ascent with the appearance of the reasoning faculties in humanity. Man, under this view, is what Sri Aurobindo elsewhere calls “a transitional being” and true human capabilities are not fully defined simply by the power of Reason, but more by the transformational capabilities of the still higher forms of consciousness of which Reason is just a partial and early indicator.
“The true and ultimate, as distinguished from the immediate or intermediate, importance of our observing, reasoning, inquiring, judging intelligence is that it prepares the human being for the right reception and right action of a Light from above which must progressively replace in him the obscure light from below that guides the animal…. All animal perceptions, sensibilities, activities are ruled by nervous and vital instincts, cravings, needs, satisfactions, of which the nexus is the life-impulse and vital desire. Man too is bound, but less bound, to this automatism of the vital nature. Man can bring an enlightened will, an enlightened thought and enlightened emotions to the difficult work of his self-development; he can more and more subject to these more conscious and reflecting guides the inferior function of desire. In proportion as he can thus master and enlighten his lower self, he is man and no longer animal.”
“When he can begin to replace desire altogether by a still greater enlightened thought and sight and will in touch with the Infinite, consciously subject to a diviner will than his own, linked to a more universal and transcendent knowledge, he has commenced the ascent towards the superman; he is on his upward march towards the Divine.”
Sri Aurobindo, The Synthesis of Yoga, Part One: The Yoga of Divine Works, Chapter 2, Self Consecration, pp. 73-74