I've always wondered whether or not fighting could be considered a science. Because to me, in science, if you employ a singular method, you should always get the same result. In actual combat, the method employed can always be countered by an individual, thus taking science out of the equation and then it becomes "personal interpretation"; making it an art all over again.
I truly doubt anyone who says their art is a science, when the reaction of their opponent changes the method they employ.
It's an art because combat is an ever evolving state.
Science is ever-evolving as well.