Kant notoriously fails to address Hume’s worry about the justification of induction, even though that is the part of Hume’s discussion of causation that he should have known best from the German translation of the first Enquiry. Some have sought to find a response to Hume on induction in the Introduction to the third Critique. I will argue that in that work Kant rather makes clear a more serious limitation on our knowledge of laws of nature than Hume’s worry about induction implies. For the latter is forgotten as soon as we go out to dinner, but Kant’s view that we can know the necessity of particular laws of nature only as part of a system that we can never fully know is an inescapable limit on our daily and scientific practices of inquiry. I will also compare Kant’s conception of our knowledge of natural laws to Josiah Royce’s famous “argument from error” to cast light on the role of an assumption of an intelligence like but greater than our own in Kant’s model.