Wolff’s Proof of the Existence of God
From Christian Wolff’s so-called “German Metaphysics”
Translation by David Forman, 2004
The 2nd Chapter
On the first grounds of our cognition
[Principle of contradiction]
Since nothing can both be and not be (§10), one cognizes that something is impossible if it contradicts what we already know is or can be, e.g., if it followed from it that a part of the whole is equal or greater than the whole […] [Or: iron wood; geometrical example.] From this one sees further that possible is what does not contain anything contradictory in it, i.e., can exist [bestehen] not only alongside other things, but also contains only such things in itself that can exist alongside each other, as, e.g., a wood plate. For being a plate and being made of wood do not contradict each other, but rather both can be at the same time.
For something to exist [etwas ist], it is not enough that it does not contain in itself anything contradictory. […]
There must thus be something in addition to possibility if something is to exist, [something] through which possibility achieves its fulfillment. And this fulfillment is just what we call existence [Würklichkeit]. In what [existence] consists—i.e., how the possible reaches existence—will be shown in its place below (§928, §929) with respect to God as the necessary and self-sufficient being [Wesen] (§565ff., §572ff., §930) with respect to other things.
The 6th Chapter
We exist (§1). Everything that exists has its sufficient reason [Grund] why it exists rather than not existing (§30); and thus we must have a sufficient reason why we exist. If we have a sufficient reason why we exist, then this reason must be found either in us or outside of us. If it is found in us, then we are necessary (§32); but if it is found in another, then that other must of course have in itself its reason why it exists, and thus it must be necessary. And in this way there is a necessary being. Whoever wants to object that the reason why we exist could also be met in something that does not have in itself the reason why it exists does not understand what a sufficient reason is. For of such a thing one must again ask further why it exists, and so one must finally arrive at something that does not require any reason outside of itself why it exists. […]
That thing which has in itself the ground [Grund] of its existence, and is therefore so constituted that it is impossible for it not to exist, is called a self-sufficient being [ein selbständiges Wesen]. And it is thus clear that there is a self-sufficient being (§928).
Whatever is self-sufficient has the ground of its existence in itself (§929). Therefore, what is not self-sufficient, but rather originates in another, has the ground of its actuality outside of itself, namely in the self-sufficient [being]. And the self-sufficient being must thus contain in itself the ground why other things that are not self-sufficient exist.
[Wolff then derives attributes of a necessary being: eternal, infinite, immaterial, simple, independent, extramundane, ground of the world, different from our soul.]
[God is a self-sufficient being, who therefore has all these attributes.]
[God’s understanding and reason]
Since God represents through his understanding all worlds (§952) and therefore everything that is possible (§953), so God’s understanding is the source of the essence [Wesen] of all things (§35) and his understanding is that which makes something possible, as he produces this representation. Namely, something is possible because it is represented by the divine understanding.