Stony Brook University

It will be further asked what the ground is for this connection [between the
subject and predicate], since there is a reality in it which does not mislead.
The reply is that it is grounded in the linking together of ideas. In response
to this it will be asked where these ideas would be if there were no mind,
and what would then become of the real foundation of this certainty of
eternal truths. This question brings us at last to the ultimate foundation of
truth, namely to that Supreme and Universal Mind who cannot fail to exist
and whose understanding is indeed the domain of eternal truths. St.
Augustine knew this and expressed it pretty forcefully. (NE 447) 55
This, I believe, is Leibniz’s most complete response to the nominalism of Hobbes and
Locke. Leibniz essentially advocates a Christian-Platonic realism about truth and ideas.
God’s mind is the region in which all ideas “exist,” and where all possibilities reside “in
advance” of fact.
And lest you should think that it is unnecessary to have recourse to this
Mind, it should be [considered] that these necessary truths contain the
determining reason and regulating principle of existent things—the laws
of the universe, in short. (NE 447) 56
Necessary truths, eternal truths, and real definitions are then the conditionalia for all
existing things. But there is another reason why these conditionalia depend on a supreme
mind. They are the a priori sources of our own knowledge.
Therefore since these necessary truths are prior to the existence of
contingent beings, they must be grounded in the existence of a necessary
substance. That is where I find the pattern for the ideas and truths which
are engraved in our soul. They are engraved there not in the form of
propositions, but rather as sources which, by being employed in particular
circumstances, will give rise to actual assertions. (NE 447) 57
This is Leibniz’s response to Locke’s claim above that “there are no extra-mental ideas
serving as patterns for our own.” It also reflects Leibniz’s doctrine of innate ideas. The
eternal, necessary truths residing in God’s mind are present in our minds as implicit
55 A.6.6.447: “Mais on demandera encore en quoi est fondée cette connexion; puisqu’il y a de la realité là
dedans qui ne trompe pas. La Reponse sera qu’elle est [fondée] dans la liaison des idées. Mais on
demandera en repliquant, où seroient ces idées, si auncun asprit n’existoit, et que deviendroit alors le
fondement reel de cette certitude des veritez eternelles. Cela nous mene enfin au dernier fondement des
veritez, savoir à cet Esprit Supreme et Universel qui ne peut manquer d’exister, dont l’Entendement, à dire
vrai, est la Region des veritez eternelles, comme St. Augustin l’a reconnu, et l’exprime d’une maniere assez
vive.” Leibniz refers the reader to Augustine’s discussion of eternal truths in De Libero Arbitrio (2.12).
56 A.6.6.447: “Et afin qu’on ne pense pas, qu’il n’est point necessaire d’y recourir, il faut considerer, que
ces verités necessaires contiennent la raison determinante et le principe regulatif des existences mêmes, et
en un mot les loix de l’Univers.”
57 A.6.6.447: “Ainsi ces verités necessaires, estant anterieures aux Existences des Estres contingens, il faut
bien qu’elles soyent fondées dans l’existence d’une substance necessaire. C’est là où je trouve l’original
des idées et des verités qui sont gravées dans nos ames, non pas en forme de propositions, mais comme des
sources dont l’application et les occasions feront naistre des enonciations actuelles.”
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