Philosophical discussion of RTM tends to focus mainly on high-level human thought, especially belief and desire. However, CCTM+RTM is applicable to a much wider range of mental states and processes. Many cognitive scientists apply it to non-human animals. For example, Gallistel and King (2009) apply it to certain invertebrate phenomena (e.g., honeybee navigation). Even confining attention to humans, one can apply CCTM+RTM to subpersonal processing. Fodor (1983) argues that perception involves a subpersonal “module” that converts retinal input into Mentalese symbols and then performs computations over those symbols. Thus, talk about a language of thought is potentially misleading, since it suggests a non-existent restriction to higher-level mental activity.