The underlying structures that are common to the world's languages bear an intriguing connection with early emerging forms of “core knowledge” (Spelke & Kinzler, 2007), which are frequently studied by infant researchers. In particular, grammatical systems often incorporate distinctions (e.g., the mass/count distinction) that reflect those made in core knowledge (e.g., the non‐verbal distinction between an object and a substance). Here, I argue that this connection occurs because non‐verbal core knowledge systematically biases processes of language evolution. This account potentially explains a wide range of cross‐linguistic grammatical phenomena that currently lack an adequate explanation. Second, I suggest that developmental researchers and cognitive scientists interested in (non‐verbal) knowledge representation can exploit this connection to language by using observations about cross‐linguistic grammatical tendencies to inspire hypotheses about core knowledge.