MN 64 includes the following teaching about a little baby:
MN 38 refers to the mental development of a child as follows:Daharassa hi, mālukyaputta, kumārassa mandassa uttānaseyyakassa kāmātipi na hoti, kuto panassa uppajjissati kāmesu kāmacchando? Anusetvevassa kāmarāgānusayo.
A little baby doesn’t even have a concept of ‘sensual pleasures’, so how could desire for sensual pleasures possibly arise in them? Yet the underlying tendency to sensual desire (kāmarāgā-anusayo) still lies within them. (Sujato)
A young tender infant lying prone does not even have the notion ‘sensual pleasures,’ so how could sensual desire arise in him? Yet the underlying tendency to sensual lust lies within him. (Bodhi)
https://suttacentral.net/mn64/en/sujato
https://suttacentral.net/mn64/en/bodhi
Therefore, it seems possible from MN 64 and MN 38 that "sensual desire" is not the inherent primitive instinctual desires for food & physical comfort a little baby has. Instead it could possibly be that "sensual desire" is something experientially conditioned & habituated from experiencing various "luxurious" pleasures after the mental & sense faculties have matured somewhat. MN 64 appears to say the "concept" or "notion" of sensual pleasure must exist before sensual desire can exist. Therefore, it appears possible that conceptual thought or "views", such as the theme (nimitta) of "beautiful", "delicious", "sexy", etc, must exist before sensual desire begins to exist. For example, MN 5 says:The mother then carries the embryo in her womb for nine or ten months with much anxiety, as a heavy burden. Then, at the end of nine or ten months, the mother gives birth with much anxiety, as a heavy burden. Then, when the child is born, she nourishes it with her own blood; for the mother’s breast-milk is called blood in the Noble One’s Discipline.
When he grows up and his faculties mature, the child plays at such games as toy ploughs, tipcat, somersaults, toy windmills, toy measures, toy carts and a toy bow and arrow.
When he grows up and his faculties mature still further, the youth enjoys himself provided and endowed with the five cords of sensual pleasure/stimulation (kāmaguṇehi), with forms cognizable by the eye… sounds cognizable by the ear… odours cognizable by the nose… flavours cognizable by the tongue… tangibles cognizable by the body that are wished for, desired, agreeable and likeable, connected with sensual desire (kāmūpasaṃhitehi) and provocative of lust (rajanīyehi).
On seeing a form with the eye, he lusts after it if it is pleasing; he dislikes it if it is unpleasing. He abides with mindfulness of the body unestablished, with a limited mind and he does not understand as it actually is the deliverance of mind and deliverance by wisdom wherein those evil unwholesome states cease without remainder. Engaged as he is in favouring and opposing, whatever feeling he feels—whether pleasant or painful or neither-painful-nor-pleasant—he delights in that feeling, welcomes it and remains holding to it. As he does so, delight arises in him. Now delight in feelings is clinging. With his clinging as condition, being comes to be; with being as condition, birth; with birth as condition, ageing and death, sorrow, lamentation, pain, grief, and despair come to be. Such is the origin of this whole mass of suffering.
Therefore, my questions for inquiry & discussion are:They will focus on the aspect (nimitta) of beauty, and because of that, lust will infect their mind.
1. Does "sensual desire" (kāmacchando) depend on thought concepts of "sensual pleasure", "beautiful", "delicious", "sexy", etc, to arise?
2. Are primitive forms of hunger & desire for food & physical comfort not included within "sensual desires"?
3. If a women solely has a desire for reproduction & motherhood, is this sensual desire (kāmacchando)?
4. Is the "craving (tanha) for forms, sounds, smells, tastes, touches" mentioned in Dependent Origination always sensual desire (kāmacchando)?
5. Or must sensual clinging (kāmupādānaṃ) occur before there is sensual desire (kāmacchando)?
And what is craving? These six are classes of craving: craving for forms, craving for sounds, craving for smells, craving for tastes, craving for tactile sensations, craving for ideas. This is called craving
And what is clinging? These four are clingings: sensuality clinging (kāmupādānaṃ), view clinging, precept & practice clinging and doctrine of self clinging. This is called clinging.
SN 12.2