He's been peeing on the potty successfully for a couple of weeks now, and so we're working on #2. We've stolen an idea from my sister: it's good to go poop in the potty because you want to let the poop join the poopy party that's happening underneath the house, and the only way to get to the poopy party is to get flushed down the toilet.
We embellished and added lots of details about all the singing and dancing that the poops do under the house, and how much the poops all enjoy the poopy party.
My lovely little logical son-of-two-engineers, however, furrows his brow and says: "But at a poopy party, the cake will get messy! You can't have poop on a cake!"
True dat.