One man owns two of the only very expensive stamps in the world. Let us say each stamp was worth a million dollars. A second man comes along and destroys stamp one. The catch is that now according to the new value the one stamp is worth more than two million, meaning the owner had a zero net loss and even had a net gain.
Is the person who destroyed stamp one responsible to pay? If so, how much? Or does the owner of the stamps have to pay him for the extra value his stamp now has?