A common pivot in debates about the nature of human language concerns the role of experience in shaping language development. While many have found young learners to be prodigious statistical learners and to display clear effects of quantity and quality of input on their ultimate language outcomes, others have focused on cases where the input is impoverished relative to the ultimate acquired knowledge. In this talk, I examine the properties of the learner that make input informative, providing a bridge between these two research traditions.