OBSERVATION AND EXPEUIMRNT. 217 



of Education, in the most enlarged sense of the term. There is not 

 properly an Art of Observing. There may be rules for observing. 

 J)ut these, like rules for inventing, are projjorly instructions for the 

 preparation of one's own mind ; for putting it into the state in which 

 it will be mnst fitted to observe, or most likely to invent. They are, 

 therefore, essentially rules of self-education, which is a different thing 

 from Logic. They do not teach how to do the thing, but how to make 

 ourselves capable of doing it. They are an art of strengthening the 

 limlTS, not an art of using them. 



The extent and minuteness of observation which may be requisite, 

 and the degree of decomposition to which it may be necessary to carry 

 the njental analysis, depend upon the particular purpose in view. To 

 ascertain the state of the whole universe at any particular m-oment is 

 impossible, but would also be useless. In making chemical experi- 

 ments, we should not think it necessary to note the position of the 

 planets; because experience has shown, as a very superficial experi- 

 ence is sufficient to show, that in such cases that circumstance is not 

 material to the j-esult : and, accordingly, in the age when men believed 

 in the occult influences of the heavenly bodies, it might have been un- 

 philosophical to omit ascertaining the precise condition of those bodies . 

 at the momeirt of the experiment. As to the degree of minuteness of 

 the mental subdivision ; if we were obliged to break down what we 

 obsen^e into its very simplest elements, that is, literally into single facts, 

 it would be difficult to say where we. should find them : we can hardly 

 ever affirm that our divisions of any kind have reached the ultimate 

 unit. But this, too, is fortunately unnecessary. The only object of the 

 mental separation is to suggest the requisite physical separation, so ■ 

 that we may either accomplish it ourselves, or seek for it in nature ; 

 and we have done enough when we have can-ied the subdivision as far 

 as the point at which we are able to see what observations or ex})eri- 

 ments we require. It is only essential, at whatever point our mental 

 decomposition of facts may for the present have stopped, that we should 

 hold ourselves ready and able to cany it further as occasion requires, 

 and should not allow the freedom of our discriminating faculty to be 

 im})risoned by the swathes and bands of ordinary classification ; as was 

 the case with all early speculative inquirers, not excepting the Greeks, 

 to whom it hardly ever occurred that what was called by one abstract 

 name might, in reality, be several phenomena, or that there was a" pos- 

 sibility of decomposing the facts of the universe into any elements but 

 those which ordinaiy language already recognized. 



§ 2. The different antecedents and consequents being, then, supposed 

 to be, so far as the case requires, ascertained and discriminated from 

 one another ; we are to inquire which is connected with which. In 

 every instance which comes under our observation, there are many 

 antecedents and many consequents. If those antecedents could not be 

 severed fi'om one another except in thought, or if those consecjuents 

 never were found apart, it would be impossible for us to distinguish 

 (a posteriori at least) the real laws, or to assign to any cause its eil'ect, 

 or to any effect its cause. To do so, we must be able to meet with 

 some of the antecedents apart from the rest, and observe what follows 

 from them; or some of the consctpients, and^ observe by what they are 

 preceded. We must, in short, follow the Baconian rule of varying 

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