Today we looked at a family of texts generated by comments in an introduction in a work of Porphyry, a 3rd century AD Platonist. Porphyry wrote that some problems about universals were interesting, and 1000 later, scholars were still debating the questions he raised!
Porphyry asked about how ‘predicables’, specifically genus and species work. Really, he was approaching universals through language. Universals are entities that can be said of other entities (in language), because they can be in those entities (in metaphysical fact). So for example I can say that your shirt is red, because redness is in your shirt. I can say that you are a human being, because human-being-ness is in you.
But what are we committed to when we talk about human-being-ness? Or redness? There is a continuum of possible views:
We saw several answers.
Plato and Augustine think that things like human-being-ness or redness are the plans, the structures of the universe. These exist independently - Augustine would say, in the mind of God. This means that knowledge of these deep structures would give us knowledge of the universe. And maybe the only way to make sense of our ordinary language, and our constant reference to things like redness is to suppose that these things actually exist, somehow.
Boethius argues that they do not exist. One argument depends on showing that if they do exist, they must be one or many - but neither description seems to work.
We also looked in detail at William of Ockham. Ockham thought that the act of the mind thinking about a thing was enough to function like a universal. When I think of human beings in general, I make my thought a ‘natural sign’ of human beings in general, just as smoke is a natural sign of fire. Smoke just stands for fire, full stop. Why can’t my thought function the same way? In effect, he is deflating the traditional problem. Why do so? Well, it is simpler, for one. But also, Ockham launches a number of attacks on realism and even conceptualism.