This paper discusses some aspects of the mental position of the penis and their relevance to castration anxiety. We know that the genital occupies an uncertain position in the representation of the body, due to the fact that the penis escapes the synthetic functions of the ego. Since we assume that this is caused partly by the processes occurring when a child learns to stand and walk, it is possible to establish a link between the phallus of the phallic phase and the imaginary phallus of the pregenital period at the time when an upright body posture is adopted.

I postulate that, at the time when a child learns to stand and walk, a protophallus is created in the form of an auxiliary leg, which performs a complex function and, as a mental fetish, forms the basis of the imaginary phallus. A bodily precursor of castration anxiety can be seen in the process described. This protophallus, the imaginary phallus and the phallus of the phallic phase are later all absorbed into the psychical representation of the penis and determine the mental image in the long term.