I Have Often Seen Videos,

of a cat jumping and opening a door,

but here is the thing how do you stop a cat from opening a door? Sven has a cat named Muldar who is a genius, 

 Muldar just would not stop opening doors, and leaving almost every door in the house open, so Sven had a cunning plan, put a trough of water in front of the door, did it work? well I did say that Muldar was a genius.