 The basic idea here is that if all matter were rational matter – of the sort that composes our ideas – then macroscopic bodies would assemble (and also decompose) just as quickly as our ideas of those bodies, but they do not. In imagination we can quickly form an idea of a house or mountain or dragon, and then recombine the components of that idea into an idea of something very different, but in nature things are more slow. They are also more steady. The three kinds of matter are more precisely “degrees of matter” (Cavendish 1668b,  4–5).[27]  Cavendish supposes that all three are so intimately blended that there is no region of matter that does not exhibit at least some mentality and perception (O’Neill 2001, xxiii–xxvi).