All right, the cats want to open the cabinet. Why? Search me. Maybe just to see what’s inside. You know they’re curious. And they figure out how to open it. This demonstrates a high order of intelligence: there are no cabinets in nature.
Now, if they really want to impress me, they’ll figure out how to move the stools so they won’t stop the door from opening all the way.
Can you imagine what cats could do, if only they had hands?