"THAT'S... HM. BUT WHAT WERE YOU GOING TO BE USED FOR? TO MAKE SO MANY VESSELS..." And ones that clearly have a mind of their own, if Kuja is any indication. He seems very intelligent and not just a fancy meat suit.

But.

Oh.

Perhaps Undyne wasn't wrong to make her vessel something else. Something without a mind. Something without autonomy. Was it wrong for Papyrus to have pursued his path with the experiment?

Surely not! He quite literally made a friend. A friend who could very easily end up helping them break the barrier, but... If he ever learned of his origins, would he be unhappy? Would he suffer a similar fate? He hadn't thought of it that way before.