  A reduplication universe is one in which the same set of qualities are distributed in the same pattern across two regions. There are both temporal and spatial versions of reduplication. We shall focus on the spatial version, as Strawson does. Suppose that Sally lives in a reduplication universe. Sally is standing in front of Bill, thinking that he has a stain on his shirt. In another region of the universe there is a qualitatively identical set of circumstances. So, there is Sally*, who is just like Sally, standing in front of Bill*, who is just like Bill, thinking that he has a stain on his shirt. For any purely qualitative condition Bill satisfies, Bill* satisfies it too. Nonetheless it seems highly intuitive that Sally is thinking about Bill and not Bill* (and Sally* is thinking about Bill* and not Bill); after all, it is Bill and not Bill* that she is standing in front of and who is the obvious source of her judgment.