HYPOTHESES. 345 



ably, if now announced, appear quite as novel* as the law of gravitation 

 appeared to the contemporaries of Newton ; possibly even more so, since 

 Newton's law, after all, was but an extension of the law of weight — that is, 

 of a generalization familiar fi'om of old, and which already comprehended 

 a not inconsiderable body of natural phenomena. The general laws of a 

 similarly commanding character, which we still look forward to the dis- 

 covery of, may not always find so much of their foundations already laid. 

 These general truths will doubtless make their first appearance in th 

 character of hypotheses ; not proved, nor even admitting of proof, in the 

 first instance, but assumed as premises for the purpose of deducing from 

 them the known laws of concrete phenomena. But this, though their ini 

 tial, can not be their final state. To entitle an hypothesis to be received 

 as one of the truths of nature, and not as a mere technical heljD to the hu 

 man faculties, it must be capable of being tested by the canons of legiti 

 mate induction, and must actually have been submitted to that test. When 

 this shall have been done, and done successfully, premises will have been 

 obtained from which all the other propositions of the science will thence- 

 forth be presented as conclusions, and the science will, by means of a new / 

 and unexpected Induction, be rendered Deductive. 



CHAPTER XIV. 



OF THE LIMITS TO THE EXPLANATION OF LAWS OF NATURE; AND OP 



HYPOTHESES. 



§ 1. The preceding considerations have led us to recognize a distinc- 

 tion between two kinds of laws, or observed uniformities in nature : ulti- 

 mate laws, and what may be termed derivative laws. Derivative laws are 

 such as are deducible from, and may, in any of the modes which we have 

 pointed out, be resolved into, other and more general ones. Ultimate laws 

 are those which can not. We are not sure that any of the uniformities 

 with Avhich we are yet acquainted are ultimate laws; but we know that 

 there must be ultimate laws ; and that every resolution of a derivative law 

 into more general laws brings us nearer to them. 



Since we are continually discovering that uniformities, not previously 

 known to be other than ultimate, are derivative, and resolvable into more 

 general laws; since (in other words) we are continually discovering the 

 explanation of some sequence which was previously known only as a fact ; 

 it becomes an interesting question whether there are any necessary limits 

 to this philosophical operation, or whether it may proceed until all the uni- 

 form sequences in nature are resolved into some one universal law. For 

 this seems, at first sight, to be the ultimatum toward which the progress 

 of induction by the Deductive Method, resting on a basis of observation 

 and experiment, is tending. Projects of this kind were universal in the 

 infancy of philosophy; any speculations which held out a less brilliant 

 prospect being in these early times deemed not worth pursuing. And the 

 idea receives so much apparent countenance from the nature of the most 

 remarkable achievements of modern science, that speculators are even now 

 frequently appearing, who profess either to have solved the problem, or to 

 suggest modes in which it may one day be solved. Even where pretensions 



* Written before the rise of the new views respecting the relation of heat to mechanical 

 force ; but confirmed rather than contradicted by them. 



