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 commence 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 matters.  And how
could I deny that these hands and this body are mine, were it
not perhaps that I compare myself to certain persons, devoid
of sense, whose cerebella are so troubled and clouded by the
violent vapours of black bile, that they constantly assure us
that they think they are kings when they are really quite
poor, or that they are clothed in purple when they are really
without covering, or who imagine that they have an earthenware
head or are nothing but pumpkins or are made of glass.  But
they are mad, and I should not be any the less insane were I
to follow examples so extravagant.

     At the same time I must remember that I am a man, and
that consequently I am in the habit of sleeping, and in my
dreams representing to myself the same things or sometimes
even less probable things, than do those who are insane in
their waking moments.  How often has it happened to me that in
the night I dreamt that I found myself in this particular
place, that I was dressed and seated near the fire, whilst in
reality I was lying undressed in bed!  At this moment it does
indeed seem to me that it is with eyes awake that I am looking
at this paper; that this head which I move is not asleep, that