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 applied to Mathematics, the Inductive stage is so short and so slight that it is performed instinctively by all people and the Deductive stage at once reached. The other branch of the Hypothetical Method, that used by Aristotle and the Greek Scientists, was, as we have seen, in reality a first and imperfect attempt to use the Inductive Method. In this Method itself, on the other hand, the main Process is the _Induction_ or derivation of a Principle or Law from accumulated Facts, while _Deduction_, or the bringing in of new Facts under the Law, is a subordinate or Secondary Process. In reality, there is but ONE Method, having several stages or _Processes_, which Processes, preponderating at different epochs, have not been clearly apprehended as necessary complements of each other, and have, hence, been regarded as different Methods. In one phase of the Anticipative or Hypothetical stage,--the assumption of basic Principles as points to reason from,--the Observation and Collection of Facts, and the Induction therefrom, were processes so imperfectly performed, that they appeared to have no existence; in another phase, that employed by Aristotle, these Processes were apparent, but still imperfectly conducted, and hence, in both cases, the Law or Principle employed for the _Deductive_ Process was liable to be defective, and therefore insufficient as a guide to the acquisition of certain knowledge. In the Inductive stage or Method, on the other hand, the Processes thus defectively employed in the former stage, the Hypothetical, are preeminently and disproportionately active, while the Deductive Process is given a very inferior position. The establishment of the just, reciprocal activity of these two Processes in intellectual investigation would secure the perfection of the _one true Scientific Method_.