As a rule ideas are in continual conflict with one another. The instincts surge upward from the depth, the inhibitions bear down from above, and between them--owing to stimuli from within and without--the sea of ideas rocks up and down, during which time another idea rises to the mirror-like surface of consciousness. Suddenly one remains on top and becomes stationary, like a buoy anchored deep to the sea’s bottom. This is the “fixed idea” of older writers and the “overvalued ideas” of modern psychotherapeutists. This idea is really deeply anchored. At the bottom of the unconscious lie the great “complexes” which impart a corresponding accent to our various ideas. An overvalued idea is anchored in a “complex” which has repressed all other “complexes.” It is accompanied or invested with a powerful affect which has stripped other ideas of their affects. A very old example--if one may so call it--of physiological insanity is the condition known as “being in love.” A German psychiatrist has taken the wholly supererogatory pains to prove anew that a lover is a kind of madman and he designates love as “physiological paranoia.” But, unfortunately, he makes no distinction between loving and being in love. But it is just through this distinction that we are enabled precisely to define the conception of an overvalued idea. Like an example from a text-book. For love is an idea whose value is generally acknowledged. We love our parents, our teacher, our country, art, our friends, etc. But as regards being in love it is quite a different matter. As to this the environment does not accept the exaggerated valuation of the emotions. Here love becomes an overvalued idea. Arguing with one who is in love about common sense, religion, education, station, or politics will not affect him in the least. He is dominated solely by the love-complex. This alone determines the resonance of his thoughts and feelings. The attraction to the chosen object has attracted all the other affects to it, has placed all the impulses at the service of one overvalued idea. He loves life but only if he be together with his beloved; he is jealous, but only with reference to the love-object; he is interested only in such matters as are in some way related to that object. The fool who is being dominated by an overvalued idea acts exactly in the same way. The lunatic who imagines himself the king of the world, and in whom a childhood wish had overpoweringly established itself as a fact in his consciousness, has interest only for such things as find access to this wish; the victim of ideas of persecution discovers in the news items of the daily papers the important communication that his enemies are laying traps for him; the unfortunate love-sick youth who imagines that Princess X wants to give him her hand in marriage sees in all sorts of advertisements of love-hungry ladies secret communications from his princess.