Freud and Psychoanalysis (Collected Works of C.G. Jung, Volume 4)
[Carl Jung and the History of Evolution]
A cursory glance at the history of evolution suffices to show that numerous complicated functions, which today must be denied all trace of sexuality, were originally nothing but offshoots of the reproductive instinct.
As we know, an important change occurred in the principles of reproduction during the ascent through the animal kingdom: the vast numbers of gametes which chance fertilization made necessary were progressively reduced in favor of assured fertilization and effective protection of the young.
The decreased production of ova and spermatozoa set free considerable quantities of energy for conversion into the mechanisms of attraction and protection of offspring, etc.
Thus we find the first stirrings of the artistic impulse in animals, but subservient to the reproductive instinct and limited to the breeding season.
The original sexual character of these biological phenomena gradually disappears as they become organically fixed and achieve functional independence.
Although there can be no doubt that music originally belonged to the reproductive sphere, it would be an unjustified and fantastic generalization to put music in the same category as sex.
Such a terminology would be tantamount to treating of Cologne cathedral in a text-book of mineralogy, on the ground that it consisted very largely of stones. ~Carl Jung, Freud and Psychoanalysis, Paragraph 79’