it may also be readily proved from the
I set forth, "Principles of Cartesian Philosophy," I. Prop. i.), or
from others of His attributes. Before treating of the subject I
will briefly show, as preliminaries, what properties must be
possessed by a Being including necessary
existence. To wit:-
eternal. For if a definite duration be assigned to it, it would beyond that definite duration be conceived as non-existent, or as not involving necessary existence, which would be contrary to its definition.
determinate, but only as infinite. For, if the nature of the said Being were determinate, and conceived as determinate, that nature would beyond the said limits be conceived as non-existent, which again is contrary to its definition.
existence, and thus one part could exist without others, and consequently be conceived as so existing. Hence the nature of the Being would be comprehended as finite, which, by what has been said, is contrary to its definition. Thus we see that, in attempting to ascribe to such a Being any imperfection, we straightway fall into contradictions. For, whether the imperfection which we wish to assign to the said Being be situate in any defect, or in limitations possessed by its nature, or in any change which it might, through deficiency of power, undergo from external causes, we are always brought back to the contradiction, that a nature which involves necessary existence, does not exist, or does not necessarily exist. I conclude, therefore-
existence, cannot have in itself any imperfection, but must express pure perfection.
perfection can it come about, that any Being should exist by its own sufficiency and force, it follows that, if we assume a Being to exist by its own nature, but not to express all perfections, we must further suppose that another Being exists, which does comprehend in itself all perfections. For, if the less powerful Being exists by its own sufficiency, how much more must the more powerful so exist?
existence belongs to its nature; such a Being which possesses in itself all perfections I will call God. If there be any Being to whose nature existence belongs, such a Being can contain in itself no imperfection, but must (by my fifth premise) express every perfection; therefore, the nature of such a Being seems to belong to God (whose existence we are bound to affirm by Premiss VI.), inasmuch as He has in Himself all perfections and no imperfections. Nor can it exist externally to God. For if, externally to God, there existed one and the same nature involving necessary existence, such nature would be twofold; but this, by what we have just shown, is absurd. Therefore there is nothing save God, but there is a single God, that involves necessary existence, which was to be proved.
Voorburg, 10 April, 1666.