Abstract argumentation provides us with methods such as gradual and Dung\nsemantics with which to evaluate arguments after potential attacks by other\narguments. Some of these methods can take intrinsic strengths of arguments as\ninput, with which to modulate the effects of attacks between arguments. Coming\nfrom abstract argumentation, these methods look only at the relations between\narguments and not at the structure of the arguments themselves. In structured\nargumentation the way an argument is constructed, by chaining inference rules\nstarting from premises, is taken into consideration. In this paper we study\nmethods for assigning an argument its intrinsic strength, based on the\nstrengths of the premises and inference rules used to form said argument. We\nfirst define a set of principles, which are properties that strength assigning\nmethods might satisfy. We then propose two such methods and analyse which\nprinciples they satisfy. Finally, we present a generalised system for creating\nnovel strength assigning methods and speak to the properties of this system\nregarding the proposed principles.\n