“The connections between the complexes of interest in money and of defecation, which seem so dissimilar, appear to be the most extensive of all. Every doctor who has practiced psychoanalysis knows that the most refractory and long-standing cases of what is described as habitual constipation in neurotics can be cured by that form of treatment. This is less surprising if we remember that that function has shown itself similarly amenable to hypnotic suggestion. But in psychoanalysis one only achieves this result if one deals with the patients’ money complex and induces them to bring it into consciousness with all its connections. It might be supposed that the neurosis is here only following an indication of common usage in speech which calls a person who keeps too careful a hold on his money “dirty” or “filthy.” But this explanation would be far too superficial. In reality, wherever archaic modes of thought have predominated or persist—in the ancient civilizations, in myths, fairy tales, and superstitions, in unconscious thinking, in dreams and in neuroses—money is brought into the most intimate relationship with dirt. We know that the gold which the devil gives his paramours turns into excrement after his departure, and the devil is certainly nothing else than the personification of the repressed unconscious instinctual life. We also know about the superstition which connects the finding of treasure with defecation, and everyone is familiar with the figure of the “shitter of ducats” (Dukatenscheisser). Indeed, even according to ancient Babylonian doctrine, gold is “the feces of Hell.” Thus in following the usage of language, neurosis, here as elsewhere, is taking words in their original, significant sense, and where it appears to be using a word figuratively, it is usually simply restoring its old meaning.
It is possible that the contrast between the most precious substance known to men and the most worthless, which they reject as waste matter (“refuse”), has led to this specific identification of gold with feces.
Yet another circumstance facilitates this equation in neurotic thought. The original erotic interest in defecation is, as we know, destined to be extinguished in later years. In those years, the interest in money makes its appearance as a new interest which had been absent in childhood. This makes it easier for the earlier impulsion, which is in process of losing its aim, to be carried over to the newly emerging aim.”
― Sigmund Freud, Character and Anal Erotism