A very different view is presented to us in the definition of the sexual instinct as a reproductive impulse, a desire for offspring.  Hegar, Eulenburg, Naecke, and Loewenfeld have accepted this as, at all events, a partial definition.[18] No one, indeed, would argue that it is a complete definition, although a few writers appear to have asserted that it is so sometimes as regards the sexual impulse in women.  There is, however, considerable mental confusion in the attempt to set up such a definition.  If we define an instinct as an action adapted to an end which is not present to consciousness, then it is quite true that the sexual instinct is an instinct of reproduction.  But we do not adequately define the sexual instinct by merely stating its ultimate object.  We might as well say that the impulse by which young animals seize food is “an instinct of nutrition.”  The object of reproduction certainly constitutes no part of the sexual impulse whatever in any animal apart from man, and it reveals a lack of the most elementary sense of biological continuity to assert that in man so fundamental and involuntary a process can suddenly be revolutionized.  That the sexual impulse is very often associated with a strong desire for offspring there can be no doubt, and in women the longing for a child—­that is to say, the longing to fulfill those functions for which their bodies are constituted—­may become so urgent and imperative that we may regard it as scarcely less imperative than the sexual impulse.  But it is not the sexual impulse, though intimately associated with it, and though it explains it.  A reproductive instinct might be found in parthenogenetic animals, but would be meaningless, because useless, in organisms propagating by sexual union.  A woman may not want a lover, but may yet want a child.  This merely means that her maternal instincts have been aroused, while her sexual instincts are still latent.  A desire for reproduction, as soon as that desire becomes instinctive, necessarily takes on the form of the sexual impulse, for there is no other instinctive mechanism by which it can possibly express itself.  A “reproductive instinct,” apart from the sexual instinct and apart from the maternal instinct, cannot be admitted; it would be an absurdity.  Even in women in whom the maternal instincts are strong, it may generally be observed that, although before a woman is in love, and also during the later stages of her love, the conscious desire for a child may be strong, during the time when sexual passion is at its highest the thought of offspring, under normally happy conditions, tends to recede into the background.  Reproduction is the natural end and object of the sexual instinct, but the statement that it is part of the contents of the sexual impulse, or can in any way be used to define that impulse, must be dismissed as altogether inacceptable.  Indeed, although the term “reproductive instinct” is frequently used, it is seldom used in a sense that we need take seriously; it is vaguely employed as a euphemism by those who wish to veil the facts of the sexual life; it is more precisely employed mainly by those who are unconsciously dominated by a superstitious repugnance to sex.