1. It has been the tendency, and, as might be proved, a necessity for science to seek the explanation of everyday facts by a generalization of those others which are less frequent and form the exception. Thus does the eruption of the volcano manifest the heat which is continually at work in the interior of the earth and to which the latter owes much of her configuration.
2. Thus does the lightning reveal a subtle power constantly busy to produce changes in the inorganic world, and, as dead languages now seldom heard were once ruling among the nations, so does a giant tooth in Siberia, or a fossil in the depth of the earth, not only bear record of the evolution of past ages, but thereby explains to us the origin of the hills and valleys which we inhabit today.
3. In this way a generalization of facts which are rare, strange, or form the exception, has been the magnetic needle guiding to all the discoveries of inductive science.
4. This method is founded upon reason and experience and thereby destroyed superstition, precedent and conventionality.
5. It is almost three-hundred years since Lord Bacon recommended this method of study, to which the civilized nations owe the greater part of their prosperity and the more valuable part of their knowledge; purging the mind from narrow prejudices, denominated theories, more effectually than by the keenest irony; calling the attention of men from heaven to earth more successfully by surprising experiments than by the most forcible demonstration of their ignorance; educating the inventive faculties more powerfully by the near prospect of useful discoveries thrown open to all, than by talk of bringing to light the innate laws of our mind.
6. The method of Bacon has seized the spirit and aim of the great philosophers of Greece and carried them into effect by the new means of observation which another age offered; thus gradually revealing a wondrous field of knowledge in the infinite space of astronomy, in the microscopic egg of embryology, and the dim age of geology; disclosing an order of the pulse which the logic of Aristotle could never have unveiled, and analyzing into formerly unknown elements the material combinations which no dialectic of the scholastics could force apart.
7. It has lengthened life; it has mitigated pain; it has extinguished diseases; it has increased the fertility of the soil; it has given new securities to the mariner; it has spanned great rivers with bridges of form unknown to our fathers; it has guided the thunderbolt from heaven to earth; it has lighted up night with the splendor of day; it has extended the range of human vision; it has multiplied the power of the human muscles; it has accelerated motion; it has annihilated distance; it has facilitated intercourse, correspondence, all friendly offices, all dispatch of business; it has enabled men to descend into the depths of the sea, to soar into the air, to penetrate securely into the noxious recesses of the earth.
8. This then is the true nature and scope of induction. But the greater the success which men have achieved in the inductive science, the more does the whole tenor of their teachings and example impress us with the necessity of observing carefully, patiently, accurately, with all the instruments and resources at our command the individual facts before venturing upon a statement of general laws.
9. To ascertain the bearing of the spark drawn from the electric machine under every variety of circumstances, that we thus may be emboldened with Franklin to address, in the form of a kite, the question to the cloud about the nature of the lightning. To assure ourselves of the manner in which bodies fall with the exactness of a Galileo, that with Newton we may dare to ask the moon about the force that fastens it to the earth.
10. In short, by the value we set upon truth, by our hope in a steady and universal progress, not to permit a tyrannical prejudice to neglect or mutilate unwelcome facts, but to rear the superstructure of science upon the broad and unchangeable basis, of full attention paid to the most isolated as well as the most frequent phenomena.