Dorothy Cheney and Robert Seyfarth have recently argued that baboons think in a propositional, discrete-valued, rule-governed, open-ended, and hierarchically structured representational medium; they conclude that baboons think in a Language of Thought, and that the primary reason they don't speak is that they lack a Theory of Mind. I argue that a representational medium which possesses these five properties could still fall significantly short of a language in its expressive power, and explore the implications for our understanding of the distinctive expressive advantages of language.