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Death is imposed on the individual life both by the conditions of its own existence and by its relations to the All-Force which manifests itself in the universe. For the individual life is a particular play of energy specialised to constitute, maintain, energise and finally to dissolve when its utility is over, one of the myriad forms which all serve, each in its own place, time and scope, the whole play of the universe. The energy of life in the body has to support the attack of the energies external to it in the universe; it has to draw them in and feed upon them and is itself being constantly devoured by them. All Matter according to the Upanishad is food, and this is the formula of the material world that “the eater eating is himself eaten”. The life organised in the body is constantly exposed to the possibility of being broken up by the attack of the life external to it or, its devouring capacity being insufficient or not properly served or there being no right balance between the capacity of devouring and the capacity or necessity of providing food for the life outside, it is unable to protect itself and is devoured or is unable to renew itself and therefore wasted away or broken; it has to go through the process of death for a new
construction or renewal.

Not only so but, again in the language of the Upanishad, the life-force is the food of the body and the body the food of the life-force; in other words, the life-energy in us both supplies the material by which the form is built up and constantly maintained and renewed and is at the same time constantly using up the substantial form of itself which it thus creates and keeps in existence. If the balance between these two operations is imperfect or is disturbed or if the ordered play of the different currents of life-force is thrown out of gear, then disease and decay intervene and commence the process of disintegration. And the very struggle for conscious mastery and even the growth of mind make the maintenance of the life more difficult. For there is an increasing demand of the life-energy on the form, a demand which is in excess of the original system of supply and disturbs the original balance of supply and demand and, before a new balance can be established, many disorders are introduced inimical to the harmony and to the length of maintenance of the life; in addition the attempt at mastery creates always a corresponding reaction in the environment which is full of forces that also desire fulfilment and are therefore intolerant of, revolt against and attack the existence which seeks to master them. There too a balance is disturbed, a more intense struggle is generated; however strong the mastering life, unless either it is unlimited or else succeeds in establishing a new harmony with its environment, it cannot always resist and triumph but must one day be overcome and disintegrated.

But, apart from all these necessities, there is the one fundamental necessity of the nature and object of embodied life itself, which is to seek infinite experience on a finite basis, and since the form, the basis by its very organisation limits the possibility of experience, this can only be done by dissolving it and seeking new forms. For the soul, having once limited itself by concentrating on the moment and the field, is driven to seek its infinity again by the principle of succession, by adding moment to moment and thus storing up a Time-experience which it calls its past; in that Time it moves through successive fields, successive experiences or lives, successive accumulations of knowledge, capacity, enjoyment, and all this it holds in subconscious or superconscious memory as its fund of past acquisition in Time. To this process change of form is essential, and for the soul involved in individual body change of form means dissolution of the body in subjection to the law and compulsion of the All-life in the material universe, to its law of supply of the material of form and demand on the material, to its principle of constant intershock and the struggle of the embodied life to exist in a world of mutual devouring. And this is the law of Death.

This then is the necessity and justification of Death, not as a denial of Life, but as a process of Life; death is necessary because eternal change of form is the sole immortality to which the finite living substance can aspire and eternal change of experience the sole infinity to which the finite mind involved in living body can attain. This change of form cannot be allowed to remain merely a constant renewal of the same form-type such as constitutes our bodily life between birth and death; for unless the form-type is changed and the experiencing mind is thrown into new forms in new circumstances of time, place and environment, the necessary variation of experience which the very nature of existence in Time and Space demands, cannot be effectuated. And it is only the process of Death by dissolution and by the devouring of life by Life, it is only the absence of freedom, the compulsion, the struggle, the pain, the subjection to something that appears to be Not-Self which makes this necessary and salutary change appear terrible and undesirable to our mortal mentality. It is the sense of being devoured, broken up, destroyed or forced away which is the sting of Death and which even the belief in personal survival of death cannot wholly abrogate.

- Sri Aurobindo