On the one hand, it's common sense (if it quacks like a duck...). But having spent a fair amount of time simulating complex things (like cells), the patterns one might induce from past behaviors don't often (completely) capture the mechanisms generating those behaviors. If this is true of, say, hepatocytes, then it's likely also true of whole animals. But this seems like a slippery slope into essentialism. At the end of the day, we have to fish or cut bait despite large swaths of uncertainty.