1. Plato On the Nature of The Good
Mind
Analogy of the Sun
The Sun
The Good
is…
that makes…
to the …
through the power of…
by providing …
a visible object
objects visible
eye
sight
light
an intelligible object
objects intelligible
soul
understanding
truth
The tree above is the visible object, the Forms (Universals) are the intelligible objects that the Good shines on. Both the Sun and the Good create their objects.

2. Aristotle On the Nature of The Good
as a transcendental property
Substance Quality Place Position Action
Quantity Relation Time Possession Passion
Socrates
is white
is in Athens
is seated
is speaking
is one
is a friend to Plato
it is noon
has a toga
is being spoken to
Is it odd that ‘good’ can be predicated in any of the 10 categories?

3. Pseudo-Dionysius on Self-Diffusion of The Good?
Father
Son
Holy Spirit
Argument, loosely, from Pseudo-Dionysius the Areopagite:
There is no contradiction in supposing an all-knowing being does not share its knowledge.
There is no contradiction in supposing an all-powerful being does not share its power.
But there seems to be a contradiction in supposing an all-good being does not share its goodness.
Therefore, an all-good being must share its goodness.
Sharing goodness requires a plurality of beings (persons?).
An all-good being must
itself be a plurality of beings (persons?), or
create other beings (persons?) with whom to share its goodness

4. Pseudo-Dionysius on Self-Diffusion of The Good
An all-good being must
itself be a plurality of beings (persons?), or
create other beings (persons?) with whom to share its goodness
So, does this Self-Diffusion principle imply that the ultimate being must be a plurality of persons (2, 3, or more) or
does it imply that the ultimate being must create a universe (multiverse)?

5. Aquinas On the Nature of The Good
God = Being = The Good
Angels
Humans
Animals
Plants
Rocks
Mud?
Formless Matter
The Great Chain of Being
Actuality
Potentiality
Aquinas gets the chain from Plotinus (his student, Porphyry), Augustine, Boethius, Pseudo-Dionysius the Areopagite, and others, and adds to it

6. Great Chain of Being The Chain is characterized by …
Gradation: the chain is composed of better and worse beings forming a linear hierarchy
Plenitude: the class of beings comprises all possible beings
Continuity: there are no gaps in the Chain (see Peter Suber’s page)
and is governed by
the Principle of Sufficient Reason (from nothing, nothing comes … a cause must have as much or more reality than its effect)
Benedict Spinoza:
Since existing is something positive, we cannot say that it has nothing as its cause (by Axiom 7 [ex nihilo, nihil fit]). Therefore we must assign some positive cause, or reason, why [a thing] exists—either an external one, i.e., one outside the thing itself, or an internal one, one comprehended in the nature and definition of the existing thing itself (Geb. I/158/4–9)
This link is just for your edification
Read just the introduction from this link
Consider Modal Argument for Existence of God
Read a recent article about whether something can come from nothing here.

7. Great Chain of Being
A few interesting links (various quality). Lovejoy’s book is considered the classic treatment:
Dr. Kip Wheeler’s Page
Wikipedia’s bit
The Great Chain in Shakespeare
The Great Chain of Being, by A. O. Lovejoy