This one goes on bottom.

"That one goes on top."

"Nuh-uh! It goes in the middle. Or else it doesn't look right."

"You're the only one who cares about looks. It needs to work. Just put it on the top."

"Hold your horses! I need to get the bottom done first. This one is the bottom, right?"

"No. This one's the bottom. That one's the top. And that other one? It goes on the top of the bottom piece."

"No no no. This one's the bottom, that one's the top, that other one goes under the top one and these all go in the middle somehow."

"Can't you see that doesn't work? It's obvious that this one's the bottom, this other one is the top, that one goes on top of the bottom one, and this one goes on top of the one that goes above the bottom one."

"Why? It makes no sense. You have to agree this one's the top."

"Okay fine. That one can go on the top. Then this one has to go on the bottom."

"Alright. Bottom. Check."

"And on top of that one, is this one."

"Okay. Got it."

"Then put this one on top of that one."

"Whoa. So you're saying this one goes on the bottom, this one is the top piece, and this one goes on top of the bottom one while that one goes on top of the one that goes on top of the bottom piece?"

"Yup."

"Okay... I guess it works"

"Now. this one on top of that one, then put the top one on."

"Alright. We did it!... But I still can't believe you made me do all that for your sandwich."

"Not just my sandwich. The perfect sandwich."