374 THE POPULAR SCIENCE MONTHLY. 



induction — by observation repeated and confirmed until tbe thing bas 

 come to be accepted as an established truth. 



Harvey was shrewd enough to perceive that such a system of rea- 

 soning, which had continued in use up to the period in which he lived, 

 did not assist in the disclosure of the secrets of Nature. He says : 

 " The method of investigating truth commonly pursued at this time is 

 to be held as erroneous and almost foolish, in which so many inquire 

 what others have said, and omit to ask whether the things themselves 

 be actually so or not ; and single universal conclusions being deduced 

 from several premises, and analogies being thence shaped out, we have 

 frequently mere verisimilitudes handed down to us instead of positive 

 truths." Men's minds must have evidently now become occupied 

 with the new system of philosophy set forth by Lord Bacon, in his 

 " Novum Organum," or " True Directions Concerning the Interpretation 

 of Nature." One of the aphorisms of this work clearly exhibits the 

 difference between the new system and the old : " There are and can be 

 only two ways of searching into and discovering truth. The one flies 

 from the senses and particulars to the most general axioms, and from 

 these principles, the truth of which it takes for settled and immovable, 

 proceeds to judgment and to the discovery of middle axioms. The 

 other derives axioms from the senses and particulars, rising by a 

 gradual and unbroken ascent, so that it arrives at the most general 

 axioms last of all." Upon system, or plan of procedure, a great deal 

 depends : look at any undertaking carried out under a good system 

 and a bad. The ancients were a long time in learning the right sys- 

 tem to adopt, but it was indeed a 'great day for science when the 

 method of reasoning by induction was introduced. Starting with par- 

 ticulars or facts which are collected from Nature by observation and 

 experiment applied in every available way, it proceeds step by step in 

 the process of generalizing until the largest and widest propositions 

 are obtained. From the proposition which has been formulated out 

 of, it may be, only a few facts, advance is made with the aid of other 

 facts to propositions of a more and more general character. The un- 

 known is brought into the domain of the known, and as this domain 

 increases, not only is the position acquired strengthened, but at the 

 same time rendered more advantageous for tbe attainment of further 

 extension. Thus the march onward proceeds, and when some general 

 law of Nature — like, for instance, gravitation, the correlation of the 

 physical forces, or, even, with a more limited bearing, reflex spinal ac- 

 tion — is discovered, a gain is made which, through reflected influence, 

 has the effect of at once immensely enlarging and perfecting the un- 

 derstanding. Truly, it may be said, the explorer by the inductive 

 method does not know whither he may be led. He dedicates himself 



" To unpathed waters — undreamed shores," 

 and follows simply the direction indicated to be taken by what hap- 

 pens to Le revealed. Guided entirely by the facts disclosed by observa- 



