Monday, April 18, 2016

If only God is perfect, then God has no proper parts

This argument is valid:

  1. Only God is perfect.
  2. Every part of God is perfect.
  3. So, every part of God is identical with God.
  4. So, God has no proper parts.
Premise (2) seems obviously true. So, we learn from the argument that if only God is perfect, then God has no proper parts.


Heath White said...

Is "perfect" a predicative adjective? Maybe someone is a perfect speller, or a perfect shoe-tier, or some calculator is perfect at arithmetic for numbers less than 100000.

Alexander R Pruss said...

Two possible interpretations:

A. x is perfect iff x is perfect at being the thing that x essentially is
B. x is perfect iff x is absolutely perfect

Which premise of the argument is plausible or not depends on the interpretation.

SMatthewStolte said...

Given A, then, is there any reason to believe that the angel Gabriel is not perfect at being essentially Gabriel?

Michael Gonzalez said...

Is your second premise supposed to be something like "If God had parts, then they would each be perfect"? If not, then premise 3 and the conclusion contradict premise 2.

On the other hand, it seems to me that the very thing which makes your premise 2 "seem obviously true" casts doubt on the overall argument and might not cohere well with premise 3. Our intuition is that, if God is the only perfect being, and He has parts, then those parts are perfect by virtue of being parts of the perfect being. So, why think they have to each BE God, rather than just being perfect by being parts of God?

Another way to put it would be this: If God is really a composite being, then we are attributing perfection to the composite, and therefore to each of the parts (unless we are imagining that they cumulatively achieve perfection BY COMPOSITION, which we clearly are NOT imagining, given the "obviousness" of something like your premise 2).

Alexander R Pruss said...


Yeah, A makes the argument less plausible. Possibly, each photon is perfect at photonicity.

Option B is better. The difficulty then is with the premise that the parts are perfect.


It's standard to say that every object is an improper part of itself. So it's trivially true that God has a part. The question is whether God has proper parts.

The other questions you raise are good ones.

CWEC Small Group said...

1. Ought implies can
2. We ought to be perfect, "even as [our] father in heaven is perfect"(Matt 5:48)
3. Therefore, we can be perfect as our father in heaven is perfect
4. Therefore, there is at least one possible world in which we are perfect as God is perfect

Perhaps God has no proper parts because there is nothing else that is perfect (I know I, at least, am not perfect), but he does not essentially have no proper parts.

Or, maybe moral perfection, even in a glorified body, is not absolute perfection- in the sense that there could only be one unique maximally great being.

Alexander R Pruss said...

Thanks: The citation of Mt 5:48 is conclusive that there is a kind of perfection that is possible for us.

James Bejon said...

I like this argument a lot--thanks! I’ve put a variant of it here:

Grateful for thoughts on it,


James Bejon said...

Here it is:

(1) God alone is worthy of worship.
(2) An object is worthy of worship if and only if it is unsurpassable in greatness.
(3) Granted (1) and (2), God and God alone is unsurpassable in greatness.
(4) God either has one part (i.e., himself, as per the claim of divine simplicity) or has more than one part.
(5) In light of (4), to make a part of God greater would be to make God greater.
(6) Granted (3) and (5), every part of God is unsurpassable in greatness.
(7) Granted (3) and (6), every part of God is identical with God.
(8) Granted (7), God has only one part, i.e., God is without parts.