Keeping in mind the ambiguities of the terms involved, we may try to identify Nietzsche’s most interesting, most considered position on decadence. One point is that we need not worry about degeneracy or mediocrity as such. On his model of individual health ‘happiness and instinct are one’.
Whatever we are we express a will to power. Whether or not this matches some external standard is hardly important. The threat we face is from demoralising ideas, morality of the weak, which is the way that decadence can infect the healthy part of the organism.
Ideas are not to cure a physiologically based decadence, which may even be hereditary. However they are vital in protecting against other ideas embodying morality of the weak. The interests of the individual and society do not have to coincide, nor do the decadence of society and that of the individual mutually imply each other. But when the instincts conflict, that is a recipe for frustration and disaster. Morality of the weak insists that there is a conflict, that the instincts are dangerous and have to be restrained. It promotes conflict by creating a confusing antithesis between happiness and knowledge. Freud’s position does this by invoking the dangerousness, and hence the fear, of the uninhibited instinct.
If the right ideas rule, ideas meant to be encapsulated in the will to power concept, then the exercise of decadent impulses will do little harm. The decadent individual will not be able to impose his own valuation. Decadence is natural, a form of defecation. Nietzsche’s argument is directed against the morality of the weak, the demoralising idea, pessimistic ideas. Otherwise we leave well alone and what is healthy will flourish. He writes:- ‘Decadence itself is not a thing that can be withstood. It is absolutely necessary and is proper to all ages & all peoples. That which must be withstood, & by all means in our power, is the spreading of the contagion among sound parts of the organism’ (Will to Power §41).
In this there is no mystery, no pseudo science. To secure against the contagion there is no need to exterminate or sterilise. Not only can we not be sure of the real causes of decadence, the chances are the wrong people will be in charge of any eugenic programme, which would certainly be dangerous. Comparable perils may be thought to face the modern world with genetic engineering. The tyranny of the weak over the strong is the thing to be feared, not the existence of decadence in the physiological sense. New power brings new possibilities for the weak and mediocre to mould the destiny of humanity with their censorship and prohibitions.
Some decadence is past cure. We permit it to exist but not to flourish to the extent of allowing its perspective to prevail over our own. We assert that to be a false perspective. If you are decadent you live in your own way. You may still contribute to the culture, perhaps uniquely. You may have one exceptional talent. Even if you reproduce, your genes may do some good, for all anyone knows. That which is destined to die will do so. But if out of your resentment you develop a perspective of so called knowledge, setting up your decadent existence as an ideal for all, identifying it with happiness, this is something that has to be argued down. We say it expresses a clear untruth that can be demonstrated as such.
Decadence has other manifestations, apart from a straight clash between instinct and self preservation. Self deception is one, obviously as involving some kind of division of aims, an unwillingness to face the truth. Part of the decadence Nietzsche identifies in Wagner, consists in the desire to dogmatise, or ‘tyrannise’ as he puts it. Presumably this is because of the dishonesty that this must involve, signalling weakness and self deception as compared with the openness of frank disputation. In Zarathustra he writes that neither a slave mor a tyrant is capable of friendship. Insofar as psychoanalysis shows intolerance and dogmatism this may suggest similar criticisms.