1. A computer-implemented method comprising: obtaining, by a computing device operable to capture images, (i) image data that describes a first scene that includes one or more objects and (ii) audio data that describes a human speech utterance, wherein the human speech utterance refers to at least a first object of the one or more objects included in the first scene; identifying, by the computing device based at least in part on the audio data and based at least in part on the image data, at least the first object that is included in the first scene and that is referred to by the human speech utterance; defining, by the computing device, a new rule that specifies a behavior of the computing device in response to future instances of identification of the first object in future image data that is different than the current image data; and controlling, by the computing device, a future operation of the computing device to comply with the new rule.