  Consider the category quality. For Suárez, quality is a concept which the mind develops based on the mind's consideration of the relations between certain concepts, such as red, blue, grammatical, and so on, on the one hand, and certain other concepts on the other, such as three meters long, yesterday, woman, and so on. In other words, quality tells us something about the first set of concepts and their relations to other concepts. But the concepts between which relations are established have instances in reality, outside the mind, though not qua concepts. Red, as universal, is not to be found outside the mind. Nonetheless, there are red things in the world and each of them is an individual instance of the universal red. This means that quality, in spite of being a concept based on the relation between concepts is nonetheless related, via those concepts, to the world outside the mind. And the same applies to the other concepts. So here we have the foundation in reality of the category quality.