The vital nature responds to life through instinct, reaction, and the pull of desire and push of aversion. The mental nature is of another kind, and it attempts to understand life through a process encompassing observation, organisation and sorting of perceptions and information, analysis and testing, and then using the knowledge so gained to attempt to act upon life successfully. To the extent that it fails in the attempt it must obviously fine tune its observations, its conclusions or its determinative action. The mind begins with its focus on the physical and vital life, but it is not restricted to them, and thus, it has its own native action in the world of ideas, as well as the capability of turning its focus higher to the spiritual basis of life. Imagination, intuition, and speculation all fall into the action of the mind either within its native province or when turned to the higher action.
Sri Aurobindo observes: “But reason seeks to understand and interpret life by one kind of symbol only, the idea; it generalises the facts of life according to its own strongly cut ideative conceptions so that it may be able to master and arrange them, and having hold of an idea it looks for its largest general application. And in order that these ideas may not be a mere abstraction divorced from the realised or realisable truth of things, it has to be constantly comparing them with facts. It has to be always questioning facts so that it may find the ideas by which they can be more and more adequately explained, ordered and managed, and it has always to be questioning ideas in order, first, to see whether they square with actual facts and, secondly, whether there are not new facts to suit which they must be modified or enlarged or which can be evolved out of them. For reason lives not only in actual facts, but in possibilities, not only in realised truths, but in ideal truths; and the ideal truth once seen, the impulse of the idealising intelligence is to see too whether it cannot be turned into a fact, cannot be immediately or rapidly realised in life. It is by this inherent characteristic that the age of reason must always be an age of progress.”
Sri Aurobindo, The Human Cycle: The Psychology of Social Development, Chapter 19, The Curve of the Rational Age, pp. 194-195