III. The Motives of Self Maintenance and Propagation

Both powers of self movement and of knowing belong inseparably together as weapons in the struggle for existence. The one developed itself along with the other, and in the degree in which these weapons win in importance in the organism, do the other more primitive ones, which are less necessary, as for example, that of fruitfulness and of vitality diminish. On the other hand, to the degree that these diminish must the importance of the first named factors for the struggle for life increase, and it must call forth their greater development.

But self movement and knowledge form by themselves by no means a sufficient weapon in the struggle. Of what use is merely the strongest muscles, the most agile joints, the sharpest senses, the greatest understanding, in this struggle, if I do not feel in me the impulse to employ them to my preservation – if the sight of food or the knowledge of danger leaves me indifferent and awakes no emotion in me? Self movement and intellectual capacity first, then, become weapons in the struggle for existence, if with them there arises a longing for the self preservation of the organism, which brings it about that all knowledge which is of importance for its existence at once produces the will to carry out the movement necessary for its existence, and therewith calls forth this movement.

Self movement and intellectual powers are without importance for the existence of the individual without his instinct of self preservation, just as this latter again is of no importance with both the former factors. All three are most intimately bound up with each other. The instinct of self preservation is the most primitive of the animal instincts and the most indispensable. Without it no animal species endowed in any degree with the power of self movement and a faculty of intelligence could maintain itself even a short time. It rules the entire life of the animal. The same social development, which ascribes the care of the intellectual faculties to particular classes, and the practical movement to others, and produces in the first an elevation of the “spirit” over the gross “matter”, goes so far in the process of isolating the intellectual faculties, that the latter, out of contempt for the “mechanical” practice which serves for the maintenance of life, comes to despise life itself. But this kind of knowledge has never as yet been able to overcome the instinct of self preservation, and to paralyze the “practise” which serves for the maintenance of life. Although many a suicide be philosophically grounded, we always, in every practical act of the denial of life, finally meet with disease or desperate social circumstances as the cause, but not a philosophical theory. Mere philosophizing cannot overcome the instinct of self preservation.

But if this is the most primitive and widely spread of all instincts it is still not the only one. It serves only for the maintenance of the individual. However long this may endure, finally it disappears without leaving any trace of its individuality behind, if it has not reproduced itself. Only those species of organisms will assert themselves in the struggle for existence, who leave a progeny behind them.

Now with the plants and the lower animals reproduction is a process which demands no power of self movement and no faculty of intelligence. That changes, however, with the animals so soon as reproduction becomes a sexual act, in which two individuals are concerned, who have to unite in order to lay either eggs and seeds (sperm) on the same spot outside of the body, or to incorporate the sperm in the body of the individual carrying the eggs. That demands a will, an impulse to find each other, to unite. Without that can the non-sexual propagation not take place, the stronger it is in the periods favorable for reproduction, so much the sooner will it take place, so much the better will be the prospects of a progeny, for the maintenance of the species. On the other hand these prospects are bad for individuals and species in whom the impulse for self reproduction is weakly developed. From a given degree of the development consequently natural selection must develop through the struggle for life an outspoken impulse to reproduction in the animal world and ever more strengthen it.

But it does not always suffice to the attainment of a numerous progeny. We have seen that in the degree in which self movement and intellectual powers grow, the number of the germs, which the individual produces, as well as its vitality, have a tendency to diminish. On the other hand the greater the division of labor, the more complicated the organism, the longer the period which is requisite for its development and its attainment to maturity. Even if a part of this period is laid in the maternal body, that has its limits. Even from considerations of space is this body not in a position to bear an organism as big as itself. It must expel the young long before that period is arrived at. From the young animals, however, the capacities for self movement and intelligence are the latest achieved, and they are mostly very weakly developed as they leave the protecting cover of the egg or the maternal body. The egg expelled by the mother is completely without motion and intelligence. Then the care for the progeny becomes an important function of the mother: the hiding and defence of the eggs anti of the young, the feeding of the latter, etc. As the impulse for reproduction, so is it with the love for the young, especially in the animal world is the maternal love developed as an indispensable means, from a certain stage of the development on, to secure the perpetuation of the species. With the impulse towards individual self preservation these impulses have nothing to do: they often come into conflict with it, and they can be so strong that they overcome it. It is clear that under otherwise equal conditions, those individuals and species have the best prospect of reproducing themselves and handing on their qualities and impulses in whom the impulse of self maintenance is not able to diminish the impulse to reproduce and protect the progeny.