such effect both in respect to its essence, and also in respect to its
existence.  (27) Now the intellect of God is the cause of both the essence
and the existence of our intellect; therefore the intellect of God in so
far as it is conceived to constitute the divine essence, differs from our
intellect both in respect to essence and in respect to existence, nor
can it in anywise agree therewith save in name, as we said before.
17:(28) The reasoning would be identical, in the case of the will, as
anyone can easily see. 

PROP. [XVIII]  God is the indwelling and not the transient cause
               of all things.

Proof.- (18:1) All things which are, are in God, and must be conceived
through God (by [xv] ), therefore (by [xvi] , Coroll. i.) God is the
cause of those things which are in him.  (2) This is our first point.
(3) Further, besides God there can be no substance (by [xiv] ), that is
nothing in itself external to God.  (4) This is our second point. God,
therefore, is the indwelling and not the transient cause of all things.
Q.E.D. 

PROP. [XIX]  God, and all the attributes of God, are eternal.

Proof.- (19:1) God (by [D.vi] ) is substance, which (by [xi] ) necessarily
exists, that is (by {[vii] ) existence appertains to its nature, or (what
is the same thing) follows from its definition; therefore, God is eternal
(by [D.viii] ).  (2) Further, by the attributes of God we must understand
that which (by [D.iv] ) expresses the essence of the divine substance, in
other words, that which appertains to substance: that, I say, should be
involved in the attributes of substance.  (3) Now eternity appertains to
the nature of substance (as I have already shown in [vii] ); therefore,
eternity must appertain to each of the attributes, and thus all are eternal.
Q.E.D.

Note.- (19:4) This proposition is also evident from the manner in which
(in [xi] )  (5) I demonstrated the existence of God; it is evident, I
repeat, from that proof, that the existence of God, like his essence,
is an eternal truth.  (6) Further (in [xix] of my "Principles of the
Cartesian Philosophy"), I have proved the eternity of God, in another
manner, which I need not here repeat.

PROP. [XX]  The existence of God and his essence are one
            and the same.

Proof.- (20:1) God (by the last [XIX] ) and all his attributes are eternal,
that is (by [D.viii] ) each of his attributes expresses existence.
(2) Therefore the same attributes of God which explain his eternal essence,
explain at the same time his eternal existence, in other words, that which
constitutes God's essence constitutes at the same time his existence.
(20:3) Wherefore God's existence and God's essence are one and the same.
Q.E.D.

Corollary I.- (20:4) Hence it follows that God's existence,
like his essence, is an eternal truth.

Corollary II.- (20:5) Secondly, it follows that God, and all the
attributes of God, are unchangeable.  (6) 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.- (21:1) 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.  (2) Now thought,
in so far as it is supposed to be an attribute of God, is necessarily
(by [xi] ) in its nature infinite.  (3) But, in so far as it possesses
the idea of God, it is supposed finite. It cannot, however, be conceived
as finite, unless it be limited by thought (by Def. ii.); but it is not
limited by thought itself, in so far as it has constituted the idea of
God (for so far it is supposed to be finite); therefore, it is limited
by thought, in so far as it has not constituted the idea of God, which
nevertheless (by [xi] ) must necessarily exist.

(21:4) We have now granted, therefore, thought not constituting the idea
of God, and, accordingly, the idea of God does not naturally follow from
its nature in so far as it is absolute thought (for it is conceived as
constituting, and also as not constituting, the idea of God), which is
against our hypothesis.  (5) Wherefore, if the idea of God expressed in
the attribute thought, or, indeed, anything else in any attribute of God
(for we may take any example, as the proof is of universal application)
follows from the necessity of the absolute nature of the said attribute,
the said thing must necessarily be infinite, which was our first point.

(21:6) Furthermore, a thing which thus follows from the necessity of the 
nature of any attribute cannot have a limited duration.  (7) For if it
can suppose a thing, which follows from the necessity of the nature of
some attribute, to exist in some attribute of God, for instance, the
 
idea of God expressed in the attribute thought, and let it be supposed
at some time not to have existed, or to be about not to exist.

(21:8) Now thought being an attribute of God, must necessarily exist
unchanged ( by [xi] , and [xx] , Coroll. ii.); and beyond the limits of
the duration of the idea of God (supposing the latter at some time not