of the soul； I feel that I should here make known to them that
having aimed at writing nothing in all this Treatise of which
I do not possess very exact demonstrations； I am obliged to
follow a similar order to that made use of by the geometers；
which is to begin by putting forward as premises all those
things upon which the proposition that we seek depends； before
ing to any conclusion regarding it。 Now the first and
principal matter which is requisite for thoroughly
understanding the immortality of the soul is to form the
clearest possible conception of it； and one which will be
entirely distinct from all the conceptions which we may have
of body； and in this Meditation this has been done。 In
addition to this it is requisite that we may be assured that
all the things which we conceive clearly and distinctly are
true in the very way in which we think them； and this could
not be proved previously to the Fourth Mediation。 Further we
must have a distinct conception of corporeal nature； which is
given partly in this Second； and partly in the Fifth and Sixth
Meditations。 And finally we should conclude from all this；
that those things which we conceive clearly and distinctly as
being diverse substances； as we regard mind and body to be；
are really substances essentially distinct one from the other；
and this is the conclusion of the Sixth Meditation。 This is
further confirmed in this same Meditation by the fact that we
cannot conceive of body excepting in so far as it is
divisible； while the mind cannot be conceived of excepting as
indivisible。 For we are not able to conceive of the half of a
mind as we can do of the smallest of all bodies； so that we
see that not only are their natures different but even in some
respects contrary to one another。 I have not however dealt
further with this matter in this treatise； both because what I
have said is sufficient to show clearly enough that the
extinction of the mind does not follow from the corruption of
the body； and also to give men the hope of another life after
death； as also because the premises from which the immortality
of the soul may be deduced depend on an elucidation of a
plete system of Physics。 This would mean to establish in
the first place that all substances generally that is to say
all things which cannot exist without being created by God￥are
in their nature incorruptible； and that they can never cease
to exist unless God； in denying to them his concurrence；
reduce them to nought； and secondly that body； regarded
generally； is a substance； which is the reason why it also
cannot perish； but that the human body； inasmuch as it differs
from other bodies； is posed only of a certain configuration
of members and of other similar accidents； while the human
mind is not similarly posed of any accidents； but is a pure
substance。 For although all the accidents of mind be changed；
although； for instance； it think certain things； will others；
perceive others； etc。； despite all this it does not emerge
from these changes another mind： the human body on the other
hand bees a different thing from the sole fact that the
figure or form of any of its portions is found to be changed。
From this it follows that the human body may indeed easily
enough perish； but the mind ＇or soul of man （I make no
distinction between them）＇ is owing to its nature immortal。
In the third Meditation it seems to me that I have
explained at sufficient length the principal argument of which
I make use in order to prove the existence of God。 But none
the less； because I did not wish in that place to make use of
any parisons derived from corporeal things； so as to
withdraw as much as I could the minds of readers from the
senses； there may perhaps have remained many obscurities
which； however； will； I hope； be entirely removed by the
Replies which I have made to the Objections which have been
set before me。 Amongst others there is； for example； this
one； 〃How the idea in us of a being supremely perfect
possesses so much objective reality ＇that is to say
participates by representation in so many degrees of being and
perfection＇ that it necessarily proceeds from a cause which is
absolutely perfect。〃 This is illustrated in these Replies by
the parison of a very perfect machine； the idea of which is
found in the mind of some workman。 For as the objective
contrivance of this idea must have some cause； i。e。 either the
science of the workman or that of some other from whom he has
received the idea； it is similarly impossible that the idea of
God which is in us should not have God himself as its cause。
In the fourth Meditation it is shown that all these
things which we very clearly and distinctly perceive are true；
and at the same time it is explained in what the nature of
error or falsity consists。 This must of necessity be known
both for the confirmation of the preceding truths and for the
better prehension of those that follow。 （But it must
meanwhile be remarked that I do not in any way there treat of
sin￥that is to say of the error which is mitted in the
pursuit of good and evil； but only of that which arises in the
deciding between the true and the false。 And I do not intend
to speak of matters pertaining to the Faith or the conduct of
life； but only of those which concern speculative truths； and
which may be known by the sole aid of the light of nature。）
In the fifth Meditation corporeal nature generally is
explained； and in addition to this the existence of God is
demonstrated by a new proof in which there may possibly be
certain difficulties also； but the solution of these will be
seen in the Replies to the Objections。 And further I show in
what sense it is true to say that the certainty of geometrical
demonstrations is itself dependent on the knowledge of God。
Finally in the Sixth I distinguish the action of the
understanding7 from that of the imagination；8 the marks by
which this distinction is made are described。 I here show
that the mind of man is really distinct from the body； and at
the same time that the two are so closely joined together that
they form； so to speak； a single thing。 All the errors which
proceed from the senses are then surveyed； while the means of
avoiding them are demonstrated； and finally all the reasons
from which we may deduce the existence of material things are
set forth。 Not that I judge them to be very useful in
establishing that which they prove； to wit； that there is in
truth a world； that men possess bodies； and other such things
which never have been doubted by anyone of sense； but because
in considering these closely we e to see that they are
neither so strong nor so evident as those arguments which lead
us to the knowledge of our mind and of God； so that these last
must be the most certain and most evident facts which can fall
within the cognizance of the human mind。 And this is the
whole matter that I have tried to prove in these Meditations；
for which reason I here omit to speak of many other questions
which I dealt incidentally in this discussion。
MEDITATIONS ON THE FIRST PHILOSOPHY
IN WHICH THE EXISTENCE OF GOD
AND THE DISTINCTION BETWEEN MIND
AND BODY ARE DEMONSTRATED。9
Meditation I。
Of the things which may be brought within the sphere of the
doubtful。
It is now some years since I detected how many were the
false beliefs that I had from my earliest youth admitted as
true； and how doubtful was everything I had since constructed
on this basis； and from that time I was convinced that I must
once for all seriously undertake to rid myself of all the
opinions which I had formerly accepted； and mence to build
anew from the foundation； if I wanted to establish any firm
and permanent structure in the sciences。 But as this
enterprise appeared to be a very great one； I waited until I
had attained an age so mature that I could not hope that at
any later date I should be better fitted to execute my design。
This reason caused me to delay so long that I should feel that
I was doing wrong were I to occupy in deliberation the time
that yet remains to me for action。 To…day； then； since very
opportunely for the plan I have in view I have delivered my
mind from every care ＇and am happily agitated by no passions＇
and since I have procured for myself an assured leisure in a
peaceable retirement； I shall at last seriously and freely
address myself to the general upheaval of all my former
opinions。
Now for this object it is not necessary that I should
show that all of these are false￥I shall perhaps never arrive
at this end。 But inasmuch as reason already persuades me that
I ought no less carefully to withhold my assent from matters
which are not entirely certain and indubitable than from those
which appear to me manifestly to be false； if I am able to
find in each one some reason to doubt； this will suffice to
justify my rejecting the whole。 And for that end it will not
be requisite that I should examine each in particular； which
would be an endless undertaking； for owing to the fact that
the destruction of the foundations of necessity brings with it
the downfall of the rest of the edifice； I shall only in the
first place attack those principles upon which all my former
opinions rested。
All that up to the present time I have accepted as most
true and certain I have learned either from the senses or
through the senses； but it is sometimes proved to me that
these senses are deceptive； and it is wiser not to trust
entirely to anything by which we have once been deceived。
But it may be that although the senses sometimes deceive
us concerning things which are hardly perceptible； or very far
away； there are yet many others to be met with as to which we
cannot reasonably have any doubt； although we recognise them
by their means。 For example； there is the fact that I am
here； seated by the fire； attired in a dressing gown； having
this paper in my hands and other similar