For if they could be changed in respect to existence, they must also be able to be changed in respect to essence--that is, obviously, be changed from true to false, which is absurd.
PROP.XXI.

All things which follow from the absolute nature of any attribute of God must always exist and be infinite, or, in other words, are eternal and infinite through the said attribute.
Proof .-- Conceive, if it be possible (supposing the proposition to be denied), that something in some attribute of God can follow from the absolute nature of the said attribute, and that at the same time it is finite, and has a conditioned existence or duration; for instance, the idea of God expressed in the attribute thought.

Now thought, in so far as it is supposed to be an attribute of God, is necessarily (by Prop.

xi.) in its nature infinite.

But, in so far as it possesses the idea of God, it is supposed finite.