Divine simplicity

In theology, the doctrine of divine simplicity says that God is without parts. The general idea of divine simplicity can be stated in this way: the being of God is identical to the "attributes" of God. In other words, such characteristics as omnipresence, goodness, truth, eternity, etc. are identical to God's being, not qualities that make up that being, nor abstract entities inhering in God as in a substance. Varieties of the doctrine may be found in Jewish, Christian, and Muslim philosophical theologians, especially during the height of scholasticism, though the doctrine's origins may be traced back to ancient Greek thought, finding apotheosis in Plotinus' Enneads as the Simplex.

In Western Christian Classical theism, God is simple, not composite, not made up of thing upon thing. Thomas Morris notes that divine simplicity can mean any or all of three different claims:

In other words, property simplicity (or metaphysical simplicity) states that the characteristics of God are not parts of God that together make up God. God is simple; God is those characteristics. For example, God does not have goodness but simply is goodness.

Spatial simplicity is endorsed by the vast majority of traditional Christian theists (who do not consider God to be a physical object). Temporal simplicity is endorsed by many theists but is highly controversial among Christian theologians. Morris describes Property simplicity as the property of having no properties, and this area is more controversial still.

In the medieval era, theologians and philosophers held to a view called "constituent ontology" whereby natures were actual constituents of things. In fact, an individual nature was more like a concrete object than an abstract object. Thus, one person's humanity was not, in this sense, the same as another person's humanity; each had his own individual human nature which was individuated by the matter out of which each man was composed. For entities which are immaterial such as angels, there is no matter to individuate their natures, so each one just is its nature. Each angel is therefore literally one of a kind.

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