What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? Name the inference rule being used: Richard is an artist or Robert is a scientist. For all x_14, if x_14 were a scientist, then x_14 is playing a game. If Richard were an artist, then Robert is playing a game.
If Robert works, then Richard is an artist can be inferred via the rewriting rule.