  According to reductive realism, which is the simplest or most ontologically parsimonious form of realism (without polyadic properties), paradigmatic relations are to be identified with ordinary, non-relational accidents—that is to say, with accidents falling under Aristotelian categories other than relation. Thus, if Simmias is taller than Socrates, this is to be explained by their respective heights, which fall under the category of quantity. Again, if Socrates is similar (say, in color) to Theaetetus, this is to be explained by Socrates’s and Theaetetus’s particular colors, which fall under the category of quality. And so on for other paradigmatic relations.