Plato, Aristotle, and the Problem of Universals

Christopher L. Holland
christopher.holland@slu.edu

Saint Louis University

February 13, 2025

Before we look at epistemology in contemporary philosophy we will take a quick look at a related question in metaphysics.

Plato and Platonic Realism

Theory of the Forms (Eternal Ideas)

How can there be many of one kind of thing?

  • What do red things have in common? Their form: Redness.
  • What do trees have in common? Their form: Treeness.
  • What do human beings have in common? Their form: Humanness.
  • What do all good things have in common? Their form: Goodness.

Theory of the Forms (Eternal Ideas)

How can there be many of one kind of thing?

Plato’s answer: Particular things (this red thing, this tree, etc.) “participate in” the Forms (redness, treeness, etc.)

  • Particular things change
  • Forms do not. They are
    • Eternal
    • Unchanging

Theory of the Forms (Eternal Ideas)

 

Neoplatonic Interpretation
The Forms are the most real things; particular things are less real than the Forms
 
Alternative Interpretation
Forms and particulars are equally real. The Forms are good objects of knowledge (because they do not change). Particulars are bad objects of knowledge (because they can change).

Innate Ideas: Knowing as Remembering

  • Plato held that learning is really a recollecting of what we learned in a previous existence.
  • Later Platonists suggest that we were created with these ideas.

Implications

  • Knowledge is only about things that do not change
  • Truth does not change
  • But, mere belief/opinion is
    • about changing things
    • about appearances

Aristotle and Aristotelian Realism

Aristotle and Aristotelian Realism

  • Rejected Plato’s Theory of the Forms
  • Forms are merely the way that particular things exist
  • Hylomorphism

Hylomorphism

  • Particular things are made up of matter and form
  • matter gives a thing “potentiality”
  • form gives a thing “actuality”
  • Example:
    • the same wood can be a tree and later a chair
    • the matter (wood) is the same but the form (tree then chair) changes
  • Abstraction: A process of the mind that separates form from matter

Scott Berman’s Flow Chart for Universals

G QST Do any nonspatiotemporal entities exist? QMI Are the nonspatiotemporal entities mindindependent? QST->QMI Yes QUE Do any universals exist? QST->QUE No R Realism QMI->R Yes C Constructivism QMI->C No QU Is being univocal? P Platonism QU->P Yes A Aristotelianism QU->A No QW Whose Mental Activity? V Theological Voluntarism QW->V God’s CR Cultural Relativism QW->CR Ours E Existentialism QW->E Mine CA Contemporary Aristotelianism QUE->CA Yes N Nominalism QUE->N No R->QU C->QW

Figure 1: Flow chart based on the appendix to Scott Berman, Platonism and the Objects of Science (London: Bloomsbury Academic, 2020).