rd to the manner of establishing definite
and exact knowledge. The Deductive, often called the _a priori_
Method--in which term the Anticipative or Hypothetical and the true
Deductive Method, seen in Mathematical investigations, are not
sufficiently discriminated--is, on the other hand, almost everywhere
denounced as essentially false, the source of all error; and we are
assured that the attempt to work it was the fault of the old world,
prior to Bacon, and the cause of its failure to secure great
intellectual results.

A distinguished thinker, Stephen Pearl Andrews, from whose writings some
of these suggestions concerning Methods have been borrowed, points out
three sources of confusion in the minds even of the learned themselves,
in connection with this subject. First, in the verbal point of view, the
terms Induction and Deduction are applied in a way directly the opposite
of that which their Etymology would indicate: _In_-duction is used for
the _De_-rivation of a Law from Facts, and _De_-duction for the
_Intro_-duction of new Facts under the Law. Secondly, the two terms
Inductive and Deductive, which are alone usually spoken of, are not
enough to designate all the processes involved in the several Scientific
Methods; and, thirdly, these terms are sometimes used to denote
_Processes_ merely, and sometimes to designate Methods which are merely
characterized by the predominance of one or the other of these
Processes.

This intricate subject of Methods may be better understood after a
statement of the following considerations. Induction, as a _Process_,
occurs whenever Facts are used as an instrument by which to discover a
Principle or Law of Nature. The Principle is derived from, or, as
Scientists have chosen to conceive it, _induced upon_ the Facts.
Deduction, as a _Process_, occurs whenever a Principle or Law of Nature
is used as an instrument by which to discover Facts. The new Facts are
ranged under, or, as it is conceived, _deduced from_ the Principle.

Each, of these Processes occurs in _every_ Scientific Method; but
different Methods are _characterised_ by that one of these two Processes
which is _put first or takes the lead in the given Method_. Thus, in
both Methods which are included in the one generally called the
Deductive, the main Process was _Deduction_, there being no perceptible
_Induction_ from Collected Facts in the proper Hypothetical or
Anticipative Method, while in the true Deductive Method, as