NOVUM ORGANON RENOVATUM. BY WILLIAM WHEWELL, D.D., MASTER OF TRINITY COLLEGE, CAMBRIDGE, AND CORRESPONDING MEMBER OF THE INSTITUTE OF FRANCE. BEING THE SECOND PART OF THE PHILOSOPHY OF THE INDUCTIVE SCIENCES. _THE THIRD EDITION, WITH LARGE ADDITIONS._ ΛΑΜΠΑΔIΑ ΕΧΟΝΤΕΣ ΔIΑΔΩΣΟΥΣIΝ ΑΛΛΗΛΟIΣ LONDON: JOHN W. PARKER AND SON, WEST STRAND. 1858. IT is to our immortal countryman; Bacon, that we owe the broad announcement of this grand and fertile principle; and the developement of the idea, that the whole of natural philosophy consists entirely of a series of inductive generalizations, commencing with the most circumstantially stated particulars, and carried up to universal laws, or axioms, which comprehend in their statements every subordinate degree of generality; and of a corresponding series of inverted reasoning from generals to particulars, by which these axioms are traced back into their remotest consequences, and all particular propositions deduced from them; as well those by whose immediate considerations we rose to their discovery, as those of which we had no previous knowledge. HERSCHEL, _Discourse on Natural Philosophy_, Art. 96. CAMBRIDGE: PRINTED BY C. J. CLAY, M.A. AT THE UNIVERSITY PRESS. {{iii}} PREFACE. EVEN if Bacon's _Novum Organon_ had possessed the character to which it aspired as completely as was possible in its own day, it would at present need renovation: and even if no such book had ever been written, it would be a worthy undertaking to determine the machinery, intellectual, social and material, by which human knowledge can best be augmented. Bacon could only divine how sciences might be constructed; we can trace, in their history, how their construction has taken place. However sagacious were his conjectures, the facts which have really occurred must give additional instruction: however large were his anticipations, the actual progress of science since his time has illustrated them in all their extent. And as to the structure and operation of the _Organ_ by which truth is to be collected from nature,--that is, the Methods by which science is to be promoted--we know that, though Bacon's general maxims are sagacious and animating, his particular precepts failed in his hands, and are now practically useless. This, perhaps, was not wonderful, seeing that they were, as I have said, mainly derived from conjectures respecting knowledge and the progress of knowledge; but at {iv} the present day, when, in several provinces of knowledge, we have a large actual progress of solid truth to look back upon, we may make the like attempt with the prospect of better success, at least on that ground. It may be a task, not hopeless, to extract from the past progress of science the elements of an effectual and substantial method of Scientific Discovery. The advances which have, during the last three centuries, been made in the physical sciences;--in Astronomy, in Physics, in