FALLACIES OF SIMPLE INSPECTION. 533 



producing an effect, implying a previous knowledge of at least one of its 

 causes. If we discover the causes of effects, it is generally by having pre- 

 viously discovered the effects of causes ; the greatest skill in devising cru- 

 cial instances for the former purpose may only end, as Bacon's physical in- 

 quiries did, in no result at all. Was it that his eagerness to acquire the 

 power of producing for man's benefit effects of practical importance to hu- 

 man life, rendering him impatient of pursuing that end by a circuitous 

 route, made even him, the champion of experiment, prefer the direct mode, 

 though one of mere observation, to the indirect, in which alone experiment 

 was possible ? Or had even Bacon not entirely cleared his mind from the 

 notion of the ancients, that " rerum cognoscere causas " was the sole ob- 

 ject of philosophy, and that to inquire into the effects of things belonged 

 to servile and mechanical arts ? 



It is worth remarking that, while the only efficient mode of cultivating 

 speculative science was missed from an undue contempt of manual opei-a- 

 tions, the false speculative views thus engendered gave in their turn a false 

 direction to such practical and mechanical aims as were suffered to exist. 

 The assumption universal among the ancients and in the Middle Ages, that 

 there were principles of heat and cold, dryness and moisture, etc., led di- 

 rectly to a belief in alchemy ; in a transmutation of substances, a change 

 from one Kind into another. Why should it not be possible to make 

 gold? Each of the characteristic properties of gold has its forma, its 

 essence, its set of conditions, which if we could discover, and learn how to 

 realize, we could superinduce that particular property upon any other sub- 

 stance, upon wood, or iron, or lime, or clay. If, then, we could effect tliis 

 with respect to every one of the essential properties of the precious metal, 

 we should have converted the other substance into gold. Nor did this, if 

 once the premises were granted, appear to transcend the real powers of 

 mankind. For daily experience showed that almost every one of the dis- 

 tinctive sensible properties of any object, its consistence, its color, its taste, 

 its smell, its shape, admitted of being totally changed by fire, or water, or 

 some other chemical agent. The fonnce of all those qualities seeming, 

 therefore, to be within human power either to produce or to annihilate, 

 not only did the transmutation of substances appear abstractedly possible, 

 but the employment of the powei*, at our choice, for practical ends, seemed 

 by no means hopeless.* 



A prejudice, universal in the ancient world, and from "which Bacon was 

 so far from being free, that it pervaded and vitiated the whole practical 

 part of his system of logic, may with good reason be ranked high in the 

 order of Fallacies of which we are now treating. 



§ 8. There remains one a priori fallacy or natural prejudice, the most 

 deeply-rooted, perhaps, of all which we have enumerated ; one which not 

 only reigned supreme in the ancient world, but still possesses almost undis- 

 puted dominion over many of the most cultivated minds ; and some of the 

 most remarkable of the numerous instances by which I shall think it neces- 

 sary to exemplify it, will be taken from recent thinkers. This is, that the 

 conditions of a phenomenon must, or at least probably will, resemble the 

 phenomenon itself. 



* It is hardly needful to remark that nothing is here intended to be said against the possi- 

 bility at some future period of making gold — by first discovering it to be a compound, and 

 putting together its different elements or ingredients. But this is a totally different idea from 

 that of the seekers of the grand arcanum. 



