erence between it and the ordinary logic is great, indeed immense.
For the ordinary logic professes to contrive and prepare helps and
guards for the understanding, as mine does; and in this one point they
agree. But mine differs from it in three points: viz., in the end aimed
at, in the order of demonstration, and in the starting-point of inquiry.

"But the greatest change I introduce is in the form itself of induction
and the judgments made thereby. For the induction of which the logicians
speak, which proceeds by simple enumeration, is a puerile thing;
concluded at hazard, is always liable to be upset by a contradictory
instance, takes into account only what is known and ordinary, and leads
to no result. Now, what the sciences stand in need of is a form of
induction which shall analyze experience and take it to pieces, and by a
due process of exclusion and rejection lead to an inevitable
conclusion."

"Now, my method, though hard to practise, is easy to explain; and it is
this: I propose to establish progressive stages of certainty. The
evidence of sense, helped and guarded by a certain process of
correction, I retain; but the mental operation which follows the act of
sense I for the most part reject; and instead of it I open and lay out a
new and certain path for the mind to proceed in, starting directly from
the simple sensuous perception."

The same dissatisfaction with mediaeval philosophy expressed itself in
Descartes. The incompetence of philosophers to solve the problems they
occupied themselves with--the anarchy which reigned in the scientific
world, where no two thinkers could agree upon fundamental points--the
extravagance of the conclusions to which some accepted premises led,
determined him to seek no more to slake his thirst at their fountains.

"And that is why, as soon as my age permitted me to quit my preceptors,"
he says, "I entirely gave up the study of letters; and resolving to seek
no other science than that which I could find in myself, or else in the
great book of the world, I employed the remainder of my youth in travel,
in seeing courts and camps, in frequenting people of diverse humors and
conditions, in collecting various experiences, and above all in
endeavoring to draw some profitable reflection from what I saw. For it
seemed to me that I should meet with more truth in the reasonings which
each man makes in his own affairs, and which, if wrong, would be
speedily punished by failure, than