Question

In Summa Theologica's article on "Whether God is altogether simple?" (and I believe in some other locations), Aquinas regularly uses the phrase "predicated of." For example:

The absolute simplicity of God may be shown in many ways... Fifth, because nothing composite can be predicated of any single one of its parts.

I don't understand exactly what this phrase means, though. Can someone explain what this argument means "in general", especially with regards to that specific phrase?

Answer 1

The phrase 'predicated of' in Aquinas's work refers to the attribution of a quality to a subject; in the case of God's simplicity, it means composite aspects cannot be attributed to God who is singular and simple.

Step-by-step explanation:

When Thomas Aquinas uses the phrase "predicated of," he is utilizing a philosophical concept to describe the process of attributing a property or quality to a subject. Specifically, in the context of Summa Theologica's article on 'Whether God is altogether simple?' the argument discusses God's simplicity. Aquinas argues that God is absolutely simple, meaning God is not composed of parts. The implication is that no attribute that applies to composite things (things made of parts) can be predicated of God because God is not composite, but singular and simple.

In other words, when Aquinas says "nothing composite can be predicated of any single one of its parts," he means that you cannot ascribe the characteristics of a composite whole to its individual parts, especially when referring to the nature of God. This is part of Aquinas's natural theology, which seeks to understand the divine by reason and observation, as opposed to revelation or church doctrine. Aquinas laid out five proofs of God's existence that engage with the concepts of potentiality and actuality, drawing upon Aristotelian philosophy to help articulate and understand the nature and attributes of God.