they would have been if we
had had the perfect use of our reason from the time of our birth, and
had never been guided by anything else.

Hence, as regarded the opinions that I had received into my belief, I
thought that, as a private person may pull down his own house to build a
finer, so I could not do better than remove them therefrom in order to
replace them by sounder, or, after I should have adjusted them to the
level of reason, to establish the same once more.

When I was younger I had studied logic, analytical geometry, and
algebra. Of these, I found that logic served rather for explaining
things we already know; while of geometry and algebra, the former is so
tied to the consideration of figures that it cannot exercise the
understanding without wearying the imagination, and the latter is so
bound down to certain rules and ciphers that it has been made a confused
and obscure art which hampers the mind instead of a science which
cultivates it. And as a state is better governed which has but few laws,
and those laws strictly observed, I believed that I should find
sufficient four precepts which follow.

The first was never to accept anything as true when I did not recognise
it clearly to be so--that is to say, carefully to avoid precipitation
and prejudice, but to include in my opinions nothing beyond that which
should present itself so clearly and distinctly to my mind that I might
have no occasion to doubt it.

The second was to divide up the difficulties which I should examine into
as many parts as possible, and as should be required for their better
solution.

The third was to conduct my thoughts in order, by beginning with the
simplest objects and those most easy to know, so as to mount little by
little, by stages, to the most complex knowledge, even supposing an
order among things which did not naturally stand in an order of
antecedent and consequent.

And the last was to make everywhere enumerations so complete, and
surveys so wide, that I should be sure of omitting nothing.

Exact observation of these precepts gave me such facility in unravelling
the questions comprehended in geometrical analysis and in algebra, that
in two or three months not only did I find my way through many which I
had formerly accounted too hard for me, but, towards the end, I seemed
to be able to determine, in those which were new to me, by what means
and to what extent it was possible to resolve them. And so I promised
my