considers that it constantly occupies half the
capacities and thoughts of the younger part of humanity, and is the
final goal of almost every human effort; that it influences adversely
the most important affairs; that it hourly disturbs the most earnest
occupations; that it sometimes deranges even the greatest intellects for
a time; that it is not afraid of interrupting the transactions of
statesmen or the investigations of men of learning; that it knows how to
leave its love-letters and locks of hair in ministerial portfolios and
philosophical manuscripts; that it knows equally well how to plan the
most complicated and wicked affairs, to dissolve the most important
relations, to break the strongest ties; that life, health, riches, rank,
and happiness are sometimes sacrificed for its sake; that it makes the
otherwise honest, perfidious, and a man who has been hitherto faithful a
betrayer, and, altogether, appears as a hostile demon whose object is to
overthrow, confuse, and upset everything it comes across: if all this is
taken into consideration one will have reason to ask--"Why is there all
this noise? Why all this crowding, blustering, anguish, and want? Why
should such a trifle play so important a part and create disturbance and
confusion in the well-regulated life of mankind?" But to the earnest
investigator the spirit of truth gradually unfolds the answer: it is not
a trifle one is dealing with; the importance of love is absolutely in
keeping with the seriousness and zeal with which it is prosecuted. The
ultimate aim of all love-affairs, whether they be of a tragic or comic
nature, is really more important than all other aims in human life, and
therefore is perfectly deserving of that profound seriousness with which
it is pursued.

As a matter of fact, love determines nothing less than the
_establishment of the next generation_. The existence and nature of the
_dramatis personae_ who come on to the scene when we have made our exit
have been determined by some frivolous love-affair. As the being, the
_existentia_ of these future people is conditioned by our instinct of
sex in general, so is the nature, the _essentia_, of these same people
conditioned by the selection that the individual makes for his
satisfaction, that is to say, by love, and is thereby in every respect
irrevocably established. This is the key of the problem. In applying it,
we shall understand it more fully if we analyse the various degrees of
lov