What did Holden and Phoebe talk about in Catcher in the Rye?

Holden confesses to Phoebe that he would like to be a catcher in the rye: he pictures a lot of children playing in a big field of rye around the edge of a cliff. Holden imagines that he would catch them if they started to go over the cliff. Holden wants to hold onto innocence. He wants other kids, like Phoebe, to hold on to their innocence and not become jaded like him.