Polymorphous perversity is Sigmund Freud's descriptive term for the non-specific nature of childhood sexuality in its primordial form.
The term points to the amorphous and changeable nature of the libido prior to being shaped in the processes of socialization and psycho-sexual development.
[1] It is this original non-specificity of the libido in early childhood that makes possible the variations of the sexual drive that later manifest as so-called 'perversions’ in the adult.
Freud theorized that some are born with unfocused pleasure/libidinal drives, deriving pleasure from any part of the body.
Freud thought that during this stage of undifferentiated impulse for pleasure, incestuous and bisexual urges are normal.