We recognize today's deep neural network (DNN) models of language behaviors as engineering achievements. However, what we know intuitively and scientifically about language shows that what DNNs are and how they are trained on bare texts, makes them poor models of mind and brain for language organization, as it interacts with infant biology, maturation, experience, unique principles, and natural law.

Christiansen & Chater (C&C) ignore the many linguistic universals that cannot be reduced to processing or cognitive constraints, some of which we present. Their claim that grammar is merely acquired language processing skill cannot account for such universals. Their claim that all other universal properties are historically and culturally based is a nonsequitur about language evolution, lacking data.

Christiansen & Chater (C&C) have taken the interactionist approach to linguistic universals to an extreme, adopting the metaphor of language as an organism. This metaphor adds no insights to five decades of analyzing language universals as the result of interaction of linguistically unique and general cognitive systems. This metaphor is also based on an outmoded view of classical Darwinian evolution and has no clear basis in biology or cognition.

While the search for the neural basis of the language of thought is a laudable enterprise, and the article by Hurford a valiant first attempt, we argue that in investigating the argument structure of natural language it will ultimately prove more fruitful to consider the restrictions forced on the system by its inherently syntactic character.

Bloom masterfully captures the state-of-the-art in the study of lexical acquisition. He also exposes the extent of our ignorance about the learning of names for non-observables. HCLMW adopts an innatist position without adopting modularity of mind; however, it seems likely that modularity is needed to bridge the gap between object names and the rest of the lexicon.

Three types of problems are raised in this commentary: On the linguistic side, we emphasize the importance of an appropriate definition of the different domains of linguistics. This is needed to define the domains (lexicon-syntax-semantics) to which transformational relations apply. We then question the concept of Broca's aphasia as a “functional” syndrome, associated with a specific lesion. Finally, we discuss evidence from functional brain imaging. The breadth and potential impact of such evidence has grown considerably in the last few years, expanding our knowledge of the multiple contributions of the “Broca's region” to phonological, lexical-semantic, and syntactic processing. “Lumping” under diagnostic labels, such as Broca's aphasia, should be replaced by more detailed linguistic and neurological descriptions of the clinical cases.