Question about the phrase "fought fire with oil" as used in the film "Spartacus"?

Question

In the film "Spartacus," the character Crassus remarks that he "fought fire with oil" in regards to him buying the Senate behind his rival's back to appoint his friend to a position of prominence.The exact exchange:Marcus Publius Glabrus: "How were you able to get my appointment without Gracchus knowing?"Marcus Licinius Crassus:"I fought fire with oil. I purchased the Senate behind his back."--------------------------------------------------Is this expression akin to "fight fire with fire"? I.e., doing the opposite of what you'd expect by using similar methods? Power with power, as the case may be? I can't find the meaning of it after doing a pretty thorough Google search. If I had to guess, I'd say it means the same as the more common expression, but I'm unsure. Maybe it's a more subtle way of saying you use similar tactics but slightly different methods to achieve an outcome that your adversary would also achieve in his own way?

Answer 1

The expression, "Fighting fire with fire" means that you are meeting force with similar force. If your opponent is yelling at you, then you yell back. If they are shooting a gun, you fire a gun back. If they are using a conventional military to attack you then you respond with your own military.

The expression, "Fighting fire with oil" is like an opposite to this. Rather than meeting force with like force, you actually use your opponent's resources and actions against them by "throwing oil on their fire". Since oil is flammable, the expression implies you are using the fire to your advantage rather than fighting against it. In the example you gave, Gracchus is a member of the Senate so presumably his weapon is politics and the power it affords him. By using this very same weapon and buying off some senators, Marcus Licinius Crassus "fought fire with oil."