 Apart from this very thin core assumption—that there are tropes—different trope theories need not have very much in  common.[1]  Most trope theorists (but not all) believe that—fundamentally—there is nothing but tropes. Most trope theorists (but, again, not all) hold that resemblance between concrete particulars is to be explained in terms of resemblance between their respective tropes. And most (but not all) hold that resemblance between tropes is determined by their primitive intrinsic nature.