The Birth of Pleasure - Tickle Tickle

When a baby first laughs, something tickles the baby, but what really causes the laugh?

In order for a ‘tickling’ to happen, it makes sense that the baby must laugh.

If the baby doesn’t laugh, then they have not, in essence, been tickled. Such an interpretation precludes the ascription of the word ‘tickling’ to the physical action of “rubbing one’s fingers at points of sensitivity on another’s body, such as about the ribs, behind the knees, or at the bottom of the feet.” Something more is required when one person tickles another person. Laughter!