If we look at the evolution of consciousness in the animal kingdom, we see that most animals are governed purely by instinctive knowledge. This is a powerful form of knowing, and allows species to pass ways of life from generation to generation, yet it does not involve a process of teaching or learning. For instance, birds instinctively know how to build a particular type of nest for the specific type of bird. Similarly, species such as the monarch butterfly pass through a 4 generation cycle in their migration from Mexico to Canada and back. We see in the higher animal species the development of a basic mental power and they can use this power to manipulate tools, and in some cases learn rudimentary human language and communicate. It is in the human being that we see the development of what Sri Aurobindo calls the “intelligent will”, the power of human reason. This power distinguishes the human being from the animal in a very clear way.
Sri Aurobindo notes: “Reason using the intelligent will for the ordering of the inner and the outer life is undoubtedly the highest developed faculty of man at his present point of evolution; it is the sovereign, because the governing and self-governing faculty in the complexities of our human existence. Man is distinguished from other terrestrial creatures by his capacity for seeking after a rule of life, a rule of his being and his works, a principle of order and self-development, which is not the first instinctive, original, mechanically self-operative rule of his natural existence. The principle he looks to is neither the unchanging, unprogressive order of the fixed natural type, nor in its process of change the mechanical evolution we see in the lower life, an evolution which operates in the mass rather than in the individual, imperceptibly to the knowledge of that which is being evolved and without its conscious cooperation. He seeks for an intelligent rule of which he himself shall be the governor and master or at least a partially free administrator. He can conceive a progressive order by which he shall be able to evolve and develop his capacities far beyond their original limits and workings; he can initiate an intelligent evolution which he himself shall determine or at least be in it a conscious instrument, more, a cooperating and constantly consulted party. The rest of terrestrial existence is helplessly enslaved and tyrannized over by its nature, but the instinct of man when he finds his manhood is to be master of his nature and free.”
Sri Aurobindo, The Human Cycle: The Psychology of Social Development, Chapter 11, The Reason as Governor of Life, pg. 102