  No-one would deny, of course, that the very same subject matter or ‘hunk of reality’ can be described in irreducibly different ways and it still be just that subject matter or piece of reality. A mass of matter could be characterized as a hurricane, or as a collection of chemical elements, or as mass of sub-atomic particles, and there be only the one mass of matter. But such different explanatory frameworks seem to presuppose different perspectives on that subject matter.