Here’s a recipe for one kind of argument from the poverty of the stimulus. To start, present an array of linguistic facts to be explained. Begin with a basic observation about form and/or meaning in some language (or, even better, an observation that crosses linguistic borders). Then show how similar forms and/or meanings crop up in other linguistic phenomena. Next, explain how one could account for the array of facts using domain-general learning mechanisms – such as distributional learning algorithms, ‘cut and paste’ operations or analogy. Follow this by introducing other phenomena that resist explanation on a learning-theoretic account. Make it clear that domain-general learning mechanisms would leave the learner short of the target language or would cause the learner to overshoot, resulting in ‘generalizations’ that are not characteristic of the natural language(s) under consideration. The next step in the recipe is to show how the entire array of linguistic phenomena can be explained using ‘abstract’ principles of Universal Grammar. These principles are not likely to be ‘learned’ because, as just witnessed, the kinds of mechanisms that are offered by learning-theoretic approaches to language development would direct learners away from the target, rather than towards it. This raises the alternative to learning, i.e., innate specification. From that point onward, the proof is in the pudding – the argument should contain an empirical demonstration that children never form the kinds of mistaken generalizations that are anticipated by learning-theoretic accounts of language acquisition. Instead, the argument should be supported by a demonstration that children form the correct generalizations, despite the apparent complexity of the phenomena, and in the absence of supporting evidence in the input. QED. There are several side issues, such as the availability of negative evidence or some substitute for it, but let us ignore such issues, and follow the recipe from the poverty of the stimulus we just sketched...