fire.

sometimes the best way to put out the fire is to let it burn until there is nothing else for it to consume. there are several ways to do it, the most famous being probably "fighting fire with fire", i.e., creating a controlled fire ahead that consumes both the oxygen and the fuel that makes the uncontrolled fire burn. this is not without risk; if one can't control the second fire, one risks having two out of control, or a bigger one. sometimes, however, risks must be taken.