Sri Aurobindo
Letters of Sri Aurobindo
Volume I - Part 2
The subconscious is the evolutionary basis in us, it is not the whole of our hidden nature, nor is it the whole origin of what we are. But things can rise from the subconscient and take shape in the conscious part and much of our smaller vital and physical instincts, movements, habits, character-forms has this source.
There are three occult sources of our action – the superconscient, the subliminal, the subconscient, but of none of them are we in control or even aware. What we are aware of is the surface being which is only an instrumental arrangement. The source of all is the general Nature,– universal Nature individualising itself in each person; for this general Nature deposits certain habits of movement, personality, character, faculties, dispositions, tendencies in us, and that, whether formed now or before our birth, is what we usually call ourselves. A good deal of this is in habitual movement and use in our known conscious part on the surface, a great deal more is concealed in the other unknown three which are below or behind the surface.
But what we are on the surface is being constantly set in motion, changed, developed or repeated by the waves of the general Nature coming in on us either directly or else indirectly through others, through circumstances, through various agencies or channels. Some of this flows straight into the conscious part and acts there, but our mind ignores its source, appropriates it and regards all that as its own; a part comes secretly into the subconscient or sinks into it and waits for an opportunity of rising up into the conscious surface; a good deal goes into the subliminal and may at any time come out – or may not, may rather rest there as unused matter. Part passes through and is rejected, thrown back or thrown out or spilt into the universal sea. Our nature is a constant activity of forces supplied to us out 
of which (or rather out of a small amount of it) we make what we will or can. What we make seems fixed and formed for good, but in reality it is all a play of forces, a flux, nothing fixed or stable; the appearance of stability is given by constant repetition and recurrence of the same vibrations and formations. That is why our nature can be changed in spite of Vivekananda’s saying and Horace’s adage and in spite of the conservative resistance of the subconscient, but it is a difficult job because the master mode of Nature is this obstinate repetition and recurrence.
As for the things in our nature that are thrown away from us by rejection but come back, it depends on where you throw them. Very often there is a sort of procedure about it. The mind rejects its mentalities, the vital its vitalities, the physical its physicalities – these usually go back into the corresponding domain of general Nature. It all stays at first, when that happens, in the environmental consciousness which we carry about with us, by which we communicate with the outside Nature, and often it persistently rushes back from there – until it is so absolutely rejected, or thrown far away as it were, that it cannot return upon us any more. But when what the thinking and willing mind rejects is strongly supported by the vital, it leaves the mind indeed but sinks down into the vital, rages there and tries to rush up again and reoccupy the mind and compel or capture our mental acceptance. When the higher vital too – the heart or the larger vital dynamis rejects it, it sinks from there and takes refuge in the lower vital with its mass of small current movements that make up our daily littleness. When the lower vital too rejects it, it sinks into the physical consciousness and tries to stick by inertia or mechanical repetition. Rejected even from there it goes into the subconscient and comes up in dreams, in passivity, in extreme tamas. The Inconscient is the last resort of the Ignorance.
As for the waves that recur from the general Nature, it is the natural tendency of the inferior forces there to try and perpetuate their action in the individual, to rebuild what he has unbuilt of their deposits in him, so they return on him, often with an increased force, even with a stupendous violence, when they 
find their influence rejected. But they cannot last long once the environmental consciousness is cleared – unless the “Hostiles” take a hand. Even then they can indeed attack, but if the sadhak has established his position in the inner self, they can only attack and retire.
It is true that we bring most of ourselves – or rather most of our predispositions, tendencies of reaction to the universal Nature – from past lives. Heredity only affects strongly the external being; besides, all the effects of heredity are not accepted even there, only those that are in consonance with what we are to be or not preventive of it at least.